KTM 50 SX MINI, 50 SX User Manual

Download

Page 1

OWNER'S MANUAL 2010

50 SX

50 SX Mini

Art. no. 3211477en

Page 2

Page 3

DEAR KTM CUSTOMER 1

DEARKTM CUSTOMER

Congratulations on your decision to purchase a KTM motorcycle. You are now the owner of a state-of-the-art sports motorcycle that will give you and your child enormous pleasure if you service and maintain it accordingly.

We wish you great pleasure riding the vehicle!

Enter the serial numbers of your vehicle below.

Chassis number ( p. 9) Dealer's stamp

Engine number ( p. 9)

The owner's manual corresponded to the latest state of this series at the time of printing. Slight deviations resulting from continuing development and design can, however, not be completely excluded.

All specifications are non-binding. KTM Sportmotorcycle AG specifically reserves the right to modify or delete technical specifications, prices, colors, forms, materials, services, designs, equipment, etc., without prior notice and without specifying reasons, to adapt these to local conditions, as well as to stop production of a particular model without prior notice. KTM accepts no liability for delivery options, deviations from illustrations and descriptions, as well as for printing and other errors. The models portrayed partly contain special equipment that does not belong to the regular scope of delivery.

ISO 9001(12 100 6061) According to the international quality management standard ISO 9001, KTM uses quality assurance processes that lead to the maximum possible quality of the products. Issued by: TÜV Management Service

KTM-Sportmotorcycle AG 5230 Mattighofen, Austria

Page 4

TABLE OF CONTENTS 2

TABLEOF CONTENTS

MEANS OF REPRESENTATION ............................................ 4

IMPORTANT INFORMATION ................................................ 5

VIEW OF VEHICLE............................................................... 7

View of the vehicle from the left front (example) ................. 7

View of the vehicle from the right rear (example) ................ 8

LOCATION OF SERIAL NUMBERS ........................................ 9

Chassis number............................................................... 9

Engine number................................................................ 9

Shock absorber part number ............................................. 9

CONTROLS....................................................................... 10

Throttle grip.................................................................. 10

Hand brake lever ........................................................... 10

Short circuit button ....................................................... 10

Fuel tap........................................................................ 10

Opening filler cap.......................................................... 10

Closing filler cap ........................................................... 11

Opening oil tank cap (50 SX Mini) .................................. 11

Closing oil tank cap (50 SX Mini).................................... 11

Choke (50 SX)............................................................... 11

Choke (50 SX Mini) ....................................................... 11

Kickstarter.................................................................... 12

Foot brake pedal ........................................................... 12

Plug-in stand ................................................................ 12

GENERAL TIPS AND HINTS ON PUTTING INTO

OPERATION...................................................................... 13

Advice on first use ......................................................... 13

Running in the engine.................................................... 14

RIDING INSTRUCTIONS .................................................... 15

Checks before putting into operation ............................... 15

Starting ........................................................................ 15

Starting up ................................................................... 16

Shifting, riding.............................................................. 16

Braking ........................................................................ 16

Stopping, parking .......................................................... 16

Refueling...................................................................... 17

Filling up with oil (50 SX Mini) ....................................... 17

SERVICE SCHEDULE......................................................... 18

Important maintenance work that must be done in an

authorized KTM workshop .............................................. 18

Important maintenance work that must be done in an

authorized KTM workshop (as additional order)................. 18

Performance of urgent inspection and care work by the

supervisory individual. ................................................... 19

MAINTENANCE WORK ON CHASSIS AND ENGINE .............. 20

Jacking up the motorcycle .............................................. 20

Removing the motorcycle from the work stand.................. 20

Adjusting the rebound damping of the shock absorber....... 20

Measuring rear wheel sag unloaded ................................. 20

Checking the static sag of the shock absorber .................. 21

Checking the riding sag of the shock absorber .................. 21

Adjusting the spring preload of the shock absorber x ...... 21

Adjusting the riding sag x............................................. 22

Removing the shock absorber x..................................... 22

Installing shock absorber x........................................... 23

Vehicle level ................................................................. 23

Adjusting the fork overhang x ....................................... 23

Adjusting seat height x ................................................ 24

Cleaning dust boots of fork legs ...................................... 24

Checking play of steering head bearing............................ 25

Adjusting play of steering head bearing x....................... 25

Removing the fork legs x.............................................. 26

Installing the fork legs x............................................... 27

Removing the lower triple clamp x ................................ 28

Installing the lower triple clamp x................................. 29

Greasing the steering head bearing x............................. 30

Dismounting the front fender .......................................... 30

Installing the front fender............................................... 31

Dismounting the start number plate ................................ 31

Installing the start number plate ..................................... 31

Handlebar position ........................................................ 32

Adjusting handlebar position x...................................... 32

Checking the play in the throttle cable............................. 32

Adjusting the play in the throttle cable x ....................... 33

Checking chain dirt ....................................................... 33

Cleaning the chain......................................................... 33

Checking the chain tension ............................................ 34

Checking the chain tension - installing rear wheel............. 34

Checking rear sprocket / engine sprocket for wear ............. 34

Adjusting chain tension.................................................. 35

Adjusting chain tension - after checking .......................... 35

Adjusting chain tension - installing rear wheel.................. 36

Adjusting the chain guide x.......................................... 36

Checking brake discs ..................................................... 36

Checking play of handbrake lever .................................... 37

Adjusting play of handbrake lever.................................... 37

Adjusting basic position of handbrake lever...................... 37

Checking the front brake fluid level ................................. 37

Adding front brake fluid x ............................................ 38

Checking the front brake linings...................................... 39

Removing front brake linings x ..................................... 39

Installing the front brake linings x................................. 39

Changing the front brake linings x................................. 40

Checking the free travel of the foot brake lever ................. 41

Adjusting basic position of foot brake pedal x ................ 41

Checking rear brake fluid level ........................................ 42

Adding rear brake fluid x.............................................. 42

Checking the rear brake linings ....................................... 43

Removing rear brake linings x....................................... 43

Installing the rear brake linings x.................................. 44

Changing the rear brake linings x.................................. 44

Removing front wheel x................................................ 45

Installing the front wheel x........................................... 45

Removing rear wheel x................................................. 46

Installing the rear wheel x ............................................ 46

Checking the tire condition............................................. 47

Checking tire air pressure ............................................... 47

Checking spoke tension.................................................. 47

Removing the seat ......................................................... 48

Mounting the seat ......................................................... 48

Cooling system .............................................................. 48

Checking the antifreeze and coolant level ........................ 49

Checking the coolant level.............................................. 49

Draining the coolant x.................................................. 50

Refilling coolant x ....................................................... 50

Removing main silencer ................................................. 51

Installing the main silencer ............................................ 51

Glass fiber yarn filling of main silencer ............................ 52

Removing the glass fiber yarn filling of the main

silencer x ................................................................... 52

Installing the glass fiber yarn filling of the main

silencer x ................................................................... 52

Removing the air filter x............................................... 52

Installing the air filter x ............................................... 53

Page 5

TABLE OF CONTENTS 3

Cleaning air filter x...................................................... 53

Carburetor - idle (50 SX) ................................................ 53

Carburetor - idle (50 SX Mini)......................................... 54

Carburetor - adjusting idle speed x (50 SX).................... 54

Carburetor - adjusting idle speed x (50 SX Mini) ............ 55

Checking oil level (50 SX Mini)....................................... 55

Bleeding oil pump x (50 SX Mini) ................................. 56

Checking gear oil level ................................................... 57

Changing the gear oil x ................................................ 57

Draining the gear oil x ................................................. 58

Filling up with gear oil x .............................................. 58

Adding gear oil x ......................................................... 58

Checking clutch engagement speed x............................ 59

Adjust the clutch engagement speed x .......................... 59

Removing centrifugal clutch x ...................................... 60

Fitting centrifugal force clutch x................................... 61

Checking/measuring clutch x........................................ 61

Dismantling centrifugal clutch x ................................... 62

Assembling centrifugal clutch x.................................... 62

TROUBLESHOOTING......................................................... 64

CLEANING........................................................................ 66

Cleaning motorcycle ...................................................... 66

STORAGE ......................................................................... 67

Storage......................................................................... 67

Putting into operation after storage ................................. 67

TECHNICAL DATA - ENGINE .............................................. 68

Capacity - gear oil.......................................................... 68

Capacity - coolant.......................................................... 68

TECHNICAL DATA - ENGINE TIGHTENING TORQUES .......... 69

TECHNICAL DATA - CARBURETOR..................................... 70

50 SX........................................................................... 70

50 SX Mini ................................................................... 70

TECHNICAL DATA - CHASSIS ............................................ 71

Tires ............................................................................ 71

Capacity - fuel............................................................... 72

TECHNICAL DATA - FORK.................................................. 73

50 SX........................................................................... 73

50 SX Mini ................................................................... 73

TECHNICAL DATA - SHOCK ABSORBER ............................. 74

50 SX........................................................................... 74

50 SX Mini ................................................................... 74

TECHNICAL DATA - CHASSIS TIGHTENING TORQUES ........ 75

OPERATING SUBSTANCES................................................ 76

AUXILIARY SUBSTANCES.................................................. 78

STANDARDS..................................................................... 80

INDEX .............................................................................. 81

Page 6

MEANS OF REPRESENTATION 4

Symbols used

The symbols used are explained in the following.

Indicates an expected reaction (e.g. of a work step or a function).

Indicates an unexpected reaction (e.g. of a work step or a function).

All work marked with this symbol requires specialist knowledge and technical understanding. In the interest of your own safety, have these jobs done in an authorized KTM workshop! There, your motorcycle will be serviced optimally by specially trained experts using the specialist tools required.

Identifies a page reference (more information is provided on the specified page).

Formats used

The typographical and other formats used are explained in the following.

Proper name Identifies a proper name.

Name

Brand™ Identifies a brand in merchandise traffic.

Identifies a protected name.

Page 7

IMPORTANT INFORMATION 5

Use definition

KTM sport motorcycles are designed and built to withstand the normal stresses and strains of competitive use. The motorcycles comply with currently valid regulations and categories of the top international motorsport organizations.

Info

The motorcycle must be used only in closed off areas remote from public road traffic.

Maintenance

A prerequisite for perfect operation and prevention of wear is that the engine and chassis maintenance and adjustment work described in the owner's manual are properly carried out. Poor adjustment and tuning of the engine and chassis can lead to damage and breakage of components. Using the motorcycle in difficult conditions such as on sand or very muddy or wet terrain can lead to above-average wear of components such as the transmission train or the brakes. For this reason, it may be necessary to service or replace worn parts before the limit specified in the service schedule is reached. Pay careful attention to the prescribed running-in period, inspection and maintenance intervals. If you observe these exactly, you will ensure a much longer service life for your motorcycle.

Warranty

The work prescribed in the service schedule must be carried out in an authorized KTM workshop only and confirmed in the customer's service record, since otherwise no warranty claims will be honored. No warranty claims can be honored for damage resulting from manipulations and/or alterations to the vehicle.

Fuel, oils, etc.

You should use the fuels, oils and greases according to specifications as listed in the owner's manual.

Spare parts, accessories

For your own safety, only use spare parts and accessory products that have been approved and/or recommended by KTM and have them installed by an authorized KTM workshop. KTM accepts no liability for other products and any resulting damage or loss. Certain spare parts and accessories are specified in parentheses in the descriptions. Your KTM dealer will be glad to advise you.

The current KTM PowerParts for your vehicle can be found on the KTM website. International KTM Website: http://www.ktm.com

Work rules

Special tools are needed for certain tasks. They are not included with the vehicle but can be ordered under the number in parentheses. Ex.: bearing puller (15112017000) During assembly, non-reusable parts (e.g. self-locking screws and nuts, seals, seal rings, O-rings, pins, lock washers) must be replaced by new parts. If a thread locker is used for the screw connections (e.g. Loctite®), follow the specific manufacturer instructions regarding its use. Parts that are to be reused after disassembly must be cleaned and checked for damage and wear. Change damaged or worn parts. After repair and maintenance, ensure that the vehicle is roadworthy.

Transport

Note

Danger of damage The parked vehicle can roll away or fall over.

– Always place the vehicle on a firm and even surface.

Note

Fire hazard Some vehicle components get very hot when the machine is driven.

– Do not place the vehicle where there are flammable or explosive substances. Do not place objects over the vehicle while it is still

warm from being run. Always let the vehicle cool first.

– Switch off the engine. – Use straps or other suitable devices to secure the motorcycle against accidents or falling over.

Page 8

IMPORTANT INFORMATION 6

Environment

Motorcycling is a wonderful sport and we naturally hope that you and your child will be able to enjoy it to the fullest. However, it is a potential problem for the environment and can lead to conflicts with other persons. But if you use your motorcycle responsibly, you can ensure that such problems and conflicts do not have to occur. To protect the future of motorcycle sport, make sure that your child uses the motorcycle legally, display environmental consciousness, and respect the rights of others.

notes/warnings

Be sure to pay attention to the notes and warnings given here.

Info

Various notes and warning stickers are attached to the vehicle. Do not remove any notes and warning stickers. If they are missing, you or others may not recognize sources of danger and may therefore be injured.

Grades of risks

Danger

Indicates immediate danger that will invariably lead to severe or even fatal injury if the appropriate measures are not taken.

Warning

Indicates immediate danger that may lead to severe or even fatal injury if the appropriate measures are not taken.

Note

Identifies a danger that will lead to considerable machine and material damage if the appropriate measures are not taken.

Warning

Indicates immediate danger that will invariably lead to environmental damage if the appropriate measures are not taken.

Owner's manual

– Carefully read this owner's manual in its entirety together with your child before letting your child ride the motorcycle for the first

time. It contains a lot of information and tips to help you and your child operate and handle the motorcycle. Only then will you find out how to customize the motorcycle ideally for your child's use and how to protect your child from injury. The owner's manual also contains important information on servicing the motorcycle.

– The owner's manual is an important component of the motorcycle and should be handed over to the new owner if the vehicle is

sold.

Page 9

VIEW OF VEHICLE 7

3.1View of the vehicle from the left front (example)

1 Hand brake lever 2 Filler cap 3 Fuel tap 4 Quick release for seat lock 5 Shock absorber compression adjustment 6 Chain guide 7 Plug-in stand

B00068-10

Page 10

VIEW OF VEHICLE 8

3.2View of the vehicle from the right rear (example)

1 Short circuit button 2 Chassis number 3 Throttle grip 4 Level viewer for brake fluid, rear 5 Foot brake pedal 6 Kickstarter

B00069-10

Page 11

LOCATION OF SERIAL NUMBERS 9

4.1Chassis number

The chassis number  is stamped on right of the steering head.

700460-01

4.2Engine number

The engine number  is stamped on the left side of the engine under the engine sprocket.

4.3Shock absorber part number

700461-01

The shock absorber part number  is stamped on the top of the shock absorber above the adjusting ring towards the rear.

700469-01

Page 12

CONTROLS 10

5.1Throttle grip

Throttle grip  is fitted on the right side of the handlebar.

700470-01

5.2Hand brake lever

Hand brake lever  is fitted on the right side of the handlebar. The hand brake lever is used to activate the front brake.

5.3Short circuit button

5.4Fuel tap

700471-01

Short circuit button  is fitted on the left side of the handlebar.

Possible states

• Short circuit button in basic position – In this position, the ignition circuit is closed, and the engine can be started.

• Short circuit button pressed – In this position, the ignition circuit is interrupted, a running engine stops, and a non-running engine will not start.

700462-01

Fuel tap  is on the left of the fuel tank.

Possible states

• Fuel tap is closed – The knurled screw is turned all the way clockwise. Fuel cannot flow out of the fuel tank.

• Fuel tap is open – The knurled screw is turned all the way counterclockwise. Fuel can flow out of the fuel tank.

5.5Opening filler cap

700463-01

– Turn the tank cap  counterclockwise and pull it up.

700465-10

Page 13

CONTROLS 11

5.6Closing filler cap

– Put the tank cap on and turn it clockwise.

Info

Run the fuel tank breather hose  without kinks.

700465-11

5.7Opening oil tank cap (50 SX Mini)

– Turn the oil tank cap  counterclockwise and pull it up.

700517-01

5.8Closing oil tank cap (50 SX Mini)

700517-10

5.9Choke (50 SX)

700464-01

– Put the oil tank cap on and turn it clockwise.

Info

Run the oil tank breather hose  without kinks.

The choke knob  is fitted on the left of the carburetor. Activating the choke function frees an opening through which the engine can draw extra fuel. This gives a richer fuel-air mixture, which is needed for a cold start.

Info

If the engine is warm, the choke function must be deactivated.

Possible states

• Choke function activated – Choke knob is in upper position. The O-ring is visible.

• Choke function deactivated – Choke knob is in lower position. No O-ring is visible.

5.10Choke (50 SX Mini)

700519-01

The choke lever  is fitted on the right of the carburetor. Activating the choke function frees an opening through which the engine can draw extra fuel. This gives a richer fuel-air mixture, which is needed for a cold start.

Info

If the engine is warm, the choke function must be deactivated.

Possible states

• Choke function activated – The choke lever is pushed up all the way.

• Choke function deactivated – The choke lever is pushed down all the way.

Page 14

CONTROLS 12

5.11Kickstarter

The kickstarter  is fitted on the right of the engine. The kickstarter can be swiveled.

Info

Before riding, swing the kickstarter inwards towards the engine.

700472-01

5.12Foot brake pedal

Foot brake pedal  is located in front of the right footrest. The foot brake pedal is used to activate the rear brake.

5.13Plug-in stand

700473-01

700474-01

Note

Danger of damage The parked vehicle can roll away or fall over.

– Always place the vehicle on a firm and even surface.

To park the motorcycle, insert the plug-in stand  in the support for the plug-in stand on the left of the vehicle.

Info

Remove the plug-in stand before riding.

Page 15

GENERAL TIPS AND HINTS ON PUTTING INTO OPERATION 13

6.1Advice on first use

Warning

Danger of accidents Physical and mental readiness of a child.

– Your child must be able to ride a bicycle and must be able to erect the vehicle independently after a fall. In addition, your

child must understand the regulations and instructions from you or from other guardians. Do not ask too much of your child; participation in a race should not be considered until your child's stamina, riding techniques and motivation are at the necessary levels. Children often underestimate or fail to recognize dangerous situations; make it clear to your child that it should not, under any circumstances, operate the vehicle without supervision and that your child may only drive at speeds that are commensurate with the child's riding abilities and the road conditions.

– Only let your child ride on the vehicle if it is physically and mentally ready to operate the vehicle.

Warning

Risk of injury Missing or poor protective clothing present an increased safety risk.

– Wear protective clothing (helmet, boots, gloves, pants and jacket with protectors) every time you ride the motorcycle. You

and your child should always used protective clothing that is in good condition and meets the legal requirements. When you ride a motorcycle, set an example for your child and wear suitable protective clothing.

Warning

Danger of crashing Impairment of handling characteristic due to different tire tread patterns on front and rear wheels.

– The front and rear wheels must be fitted with tires with similar tread patterns to prevent loss of control over the vehicle.

Warning

Danger of accidents Critical riding behavior due to inappropriate riding.

– Ensure that your child adjusts the riding speed to the road conditions and to his or her riding abilities.

Warning

Danger of accidents Accident risk caused by presence of a passenger.

– Your vehicle is not designed to carry passengers. Do not ride with a passenger.

Warning

Danger of accidents Brake system failure.

– If the foot brake pedal is not released, the brake linings drag permanently. The rear brake can fail due to overheating.

Ensure that your child raises his or her foot from the foot brake pedal when the child does not want to brake.

Warning

Danger of accidents Destruction of chassis components.

– Do not exceed the maximum allowable rider weight.

Warning

Risk of misappropriation Usage by unauthorized persons.

– Never leave the vehicle while the engine is running. Secure the vehicle against use by unauthorized persons.

Info

When using your motorcycle, remember that others may feel disturbed by excessive noise.

– Make sure that the pre-delivery inspection work has been carried out by an authorized KTM workshop.

You receive a delivery certificate and the service record at vehicle handover.

– Carefully read the entire owner's manual together with your child before going for the first ride.

Info

Pay special attention to the safety warnings and injury risks. Explain to your child the techniques of riding and falling, e.g. how shifting weight can influence handling characteristics.

– Familiarize your child with the controls. – Adjust the basic position of the handbrake lever. ( p. 37)

–

Adjust the basic position of the foot brake pedal. x ( p. 41)

– Before using the vehicle for the first time, ensure that the basic settings of the chassis are suitable for the weight of your child. – Accustom your child to the handling of the motorcycle on suitable terrain, preferably on a large open meadow.

Page 16

GENERAL TIPS AND HINTS ON PUTTING INTO OPERATION 14

Info

To give your child a feel for the brake, you should push your child at first. Do not start the engine until your child can is able to apply the necessary brake pressure. At the start, let your child ride to another person who can help him or her stop and turn.

– Erect obstacles for your child to navigate around to accustom your child to handling the vehicle. – Your child should also try to ride as slowly as possible and in a standing position to get a better feeling for the vehicle. – Do not let your child try any off-road rides that would exceed the ability and experience of your child. – Your child should hold the handlebar firmly with both hands and keep his or her feet on the footrests when riding. – Do not exceed the maximum allowable rider weight.

Guideline

Maximum rider weight < 35 kg (< 77 lb.) Maximum rider size < 130 cm (< 51.2 in)

– Check the spoke tension. ( p. 47)

Info

The spoke tension must be checked after riding the motorcycle for half an hour.

– Run the engine in. ( p. 14)

6.2Running in the engine

– During the running-in phase, do not exceed the specified engine performance.

Guideline

Maximum engine performance

During the first 3 service hours < 70 % During the first 5 service hours < 100 %

– Avoid fully opening the throttle!

Page 17

RIDING INSTRUCTIONS 15

7.1Checks before putting into operation

Info

Make sure that the motorcycle is in a perfect technical condition before use.

Info

In the interests of riding safety, make it your own and your child's habit to perform a general check before going for a ride. Insist that your child perform the general checks himself or herself.

– Check the gear oil level. ( p. 57)

(50 SX Mini)

– Check the oil level. ( p. 55) – Check the chain tension. ( p. 34) – Check the chain dirt accumulation. ( p. 33) – Check the tire condition. ( p. 47) – Check the tire air pressure. ( p. 47) – Check the front brake fluid level. ( p. 37) – Check the rear brake fluid level. ( p. 42) – Check the front brake linings. ( p. 39) – Check the rear brake linings. ( p. 43) – Check the function of the brake system. – Check the coolant level. ( p. 49) – Check the settings of all controls and ensure that they can be operated smoothly. – Check the functioning of the electrical equipment.

7.2Starting

Danger

Danger of poisoning Exhaust gases are poisonous and can result in unconsciousness and/or death.

– When running the engine, always make sure there is sufficient ventilation, and do not start or run the engine in a closed

space without an effective exhaust extraction system.

Note

Engine failure High engine speeds in cold engines have a negative effect on the service life of the engine.

– Always warm up the engine at low engine speeds.

Info

If the motorcycle is unwilling to start, the cause can be old fuel in the float chamber. The flammable elements of the fuel evaporate after a long time of standing. If the float chamber is filled with fresh fuel, the engine starts immediately.

– Turn the knurled screw on the fuel tap all the way counterclockwise.

Fuel can flow from the fuel tank to the carburetor.

– Remove the motorcycle from the stand.

The engine is cold

(50 SX)

– Pull the choke knob fully out and turn it by max. ¼ turn.

(50 SX Mini)

– Push the choke lever up all the way.

– Forcefully step on the kickstarter, pushing it all the way forward.

Info

Do not open the throttle.

Page 18

RIDING INSTRUCTIONS 16

7.3Starting up

Info

The plug-in stand must be removed before you start your journey.

– Open the throttle carefully.

7.4Shifting, riding

Info

If you hear unusual noises while riding, stop immediately, switch off the engine and contact an authorized KTM workshop.

– If the choke function was activated, deactivate it after the engine has warmed up. – When you reach maximum speed after fully opening the throttle, turn back the throttle to about ¾ of its range. The speed hardly

drops, but the fuel consumption falls considerably. – Your child should always open the throttle only as much as the engine can handle – abruptly opening the throttle increases fuel

consumption. – Your child should switch off the engine if he or she expects to be standing for a long time.

Guideline

≥ 2 min

7.5Braking

Warning

Danger of accidents If you brake too hard, the wheels can lock.

– Adapt your braking to the traffic situation and the road conditions.

Warning

Danger of accidents Reduced braking efficiency caused by spongy pressure point of front or rear brake.

– Check the brake system and do not continue riding. (Your authorized KTM workshop will be glad to help.)

Warning

Danger of accidents Reduced braking efficiency due to wet or dirty brakes.

– Clean or dry dirty or wet brakes by riding and braking gently.

– On sandy, wet or slippery surfaces, use the rear brake. – Braking should always be completed before you go into a bend.

7.6Stopping, parking

Warning

Risk of misappropriation Usage by unauthorized persons.

– Never leave the vehicle while the engine is running. Secure the vehicle against use by unauthorized persons.

Warning

Danger of burns Some vehicle components get very hot when the machine is driven.

– Do not touch hot components such as exhaust system, radiator, engine, shock absorber and brakes. Allow these compo-

nents to cool down before starting work on them.

Note

Danger of damage The parked vehicle can roll away or fall over.

– Always place the vehicle on a firm and even surface.

Note

Fire hazard Some vehicle components get very hot when the machine is driven.

– Do not place the vehicle where there are flammable or explosive substances. Do not place objects over the vehicle while it is still

warm from being run. Always let the vehicle cool first.

Page 19

RIDING INSTRUCTIONS 17

Note

Material damage Damage and destruction of components due to excessive load.

– The plug-in stand is designed for the weight of the motorcycle only. You or your child should not sit on the motorcycle when it is

standing on the plug-in stand. The plug-in stand and/or the frame could be damaged and the motorcycle could fall over.

– Brake the motorcycle. – Press and hold the short circuit button while the engine is idling until the engine stops. – Turn the knurled screw on the fuel tap all the way clockwise. – Park the motorcycle on firm ground.

7.7Refueling

Danger

Fire hazard Fuel can easily catch fire.

– Never fill up the vehicle near open flames or burning cigarettes, and always switch off the engine first. Be careful that no

fuel is spilt, especially on hot vehicle components. Clean up spilt fuel immediately.

– Fuel in the fuel tank expands when warm and can escape if the tank is overfilled. See specifications on filling up with fuel.

Warning

Danger of poisoning Fuel is poisonous and a health hazard.

– Avoid contact of the fuel with skin, eyes and clothing. Do not inhale fuel vapors. If fuel gets into your eyes, rinse imme-

diately with water and contact a doctor. Wash affected skin areas immediately with soap and water. If fuel is swallowed, contact a doctor immediately. Change clothing that has come into contact with fuel.

Warning

Environmental hazard Improper handling of fuel is a danger to the environment.

– Do not allow fuel to get into the ground water, the ground, or the sewage system.

– Switch off the engine. – Open the filler cap. ( p. 10) – Fill the fuel tank with fuel up to measurement .

Guideline

Measurement of  35 mm (1.38 in)

400214-10

7.8Filling up with oil (50 SX Mini)

Fuel tank capacity, approx. (50 SX Mini)

Fuel tank capacity, approx. (50 SX)

– Close the filler cap. ( p. 11)

2.0 l (2.1 qt.) Super unleaded (ROZ 95 / RON 95 /

2.3 l (2.4 qt.) Super unleaded gasoline, mixed with

Warning

Engine failure If the vehicle is run without 2-stroke oil in the tank, the result is engine failure.

– The oil tank must always be filled up to the MIN mark.

PON 91) ( p. 77)

2-stroke engine oil (1:60) ( p. 77)

700518-01

– Switch off the engine. – Open the oil tank cap. ( p. 11) – Fill the oil tank at least up to the MIN mark .

Guideline

MIN mark Sufficient for a single tank filling

Oil tank contents ca.

– Close the oil tank cap. ( p. 11)

0.2 l (0.2 qt.) 2-stroke engine oil ( p. 76)

Page 20

SERVICE SCHEDULE 18

8.1Important maintenance work that must be done in an authorized KTM workshop

S20A S40A

engine

Change the gear oil. x ( p. 57) Check spark plug and replace if required. x Clean spark plug connectors and check for tightness. x

• •

Check engine mounting screws for tightness. • •

Check the clutch engagement speed. x ( p. 59)

• •

carburetor Check intake flange and carburetor connection boot for cracks and leakage. •

Check idle. • • Check vent hoses for damage and routing without sharp bends. •

Attachments Check the cooling system for leakage. •

Check the antifreeze and coolant level. ( p. 49) • Check exhaust system for leakage and looseness. • • Check throttle cables for damage, smooth operation and routing without sharp bends. •

Clean the air filter. x ( p. 53)

• •

Brakes Check the front brake linings. ( p. 39) •

Check the rear brake linings. ( p. 43) • Check the brake discs. ( p. 36) • Check the front brake fluid level. ( p. 37) • • Check the rear brake fluid level. ( p. 42) • • Check brake lines for damage and leakage. • Check the play of the handbrake lever. ( p. 37) • • Check the free travel of the foot brake lever. ( p. 41) • • Check the function of the brake system. • • Check screws and guide bolts of brake system for tightness. • •

Chassis

Check shock absorber and fork for leakage and functioning. x

• • Clean dust boots of fork legs. ( p. 24) • • Check swingarm bearing. • Check play of steering head bearing. ( p. 25) • Check all screws to see if they are tight. • •

Wheels Check the spoke tension. ( p. 47) • •

Check rim run-out. • • Check the tire condition. ( p. 47) • • Check the tire air pressure. ( p. 47) • • Check the chain wear. • • Check the chain tension. ( p. 34) • • Clean the chain. ( p. 33) • • Check wheel bearing for play. • • Clean and grease adjusting screws of chain adjuster. • •

•

S20A: every 20 service hours S40A: every 40 service hours

8.2Important maintenance work that must be done in an authorized KTM workshop (as additional order)

S20A S40A S80A J1A

Check/set the carburetor components. (50 SX Mini) x Check/set the carburetor components. (50 SX) x Check the reed valve housing, diaphragm and intake flange. x Check/measure the clutch. x ( p. 61) Checking wear of clutch drum. x Determine the piston/cylinder mounting clearance. x Check the seating of the piston pin. x

• • •

•

Page 21

SERVICE SCHEDULE 19

S20A S40A S80A J1A

Check main bearing of the crankshaft. x Check radial clearance of conrod bearing. x Change crankshafts and conrod bearings. x Service the fork. x Service the shock absorber. x Clean and lubricate swingarm bearing. x Grease the steering head bearing. x ( p. 30) Change the glass fiber yarn filling of the main silencer. x Change the front brake fluid. x Change the rear brake fluid. x

S20A: every 20 service hours S40A: every 40 service hours S80A: every 80 service hours J1A: annually

8.3Performance of urgent inspection and care work by the supervisory individual.

Check the gear oil level. ( p. 57) • Check the front brake fluid level. ( p. 37) • Check the rear brake fluid level. ( p. 42) • Check the front brake linings. ( p. 39) • Check the rear brake linings. ( p. 43) • Check and adjust throttle cables. • Bleed fork legs. • Clean dust boots of fork legs. ( p. 24) • Clean the chain. ( p. 33) • Check the chain tension. ( p. 34) • Check the chain wear. • Check rear sprocket / engine sprocket for wear. ( p. 34) •

Clean the air filter. x ( p. 53)

Check the tire air pressure. ( p. 47) • Check the tire condition. ( p. 47) • Check the coolant level. ( p. 49) • Check all controls for smooth operation. • Check braking. • Check all screws, nuts and hose clamps regularly for tightness. •

• • •

• •

•

• • •

•

NB1A

•

NB1A: Depending on conditions of use according to requirements.

Page 22

MAINTENANCE WORK ON CHASSIS AND ENGINE 20

00AA

9.1Jacking up the motorcycle

Note

Danger of damage The parked vehicle can roll away or fall over.

– Always place the vehicle on a firm and even surface.

– Jack up the motorcycle underneath the engine.

Work stand (54829055000)

– Secure the motorcycle against falling over.

700475-01

9.2Removing the motorcycle from the work stand

Note

Danger of damage The parked vehicle can roll away or fall over.

– Always place the vehicle on a firm and even surface.

– Remove the motorcycle from the work stand. – Remove the work stand.

9.3Adjusting the rebound damping of the shock absorber

Danger

Danger of accidents Disassembly of pressurized parts can lead to injury.

– The shock absorber is filled with high density nitrogen. Adhere to the description provided. (Your authorized KTM workshop

will be glad to help.)

– Turn adjusting screw  clockwise to the last perceptible click. – Turn back counterclockwise by the number of clicks corresponding to the shock

absorber type. Guideline

Rebound damping (50 SX)

Standard 10 clicks

Rebound damping (50 SX Mini)

Standard 12 clicks

700476-01

Info

Turn clockwise to increase damping, turn counterclockwise to reduce suspension damping.

9.4Measuring rear wheel sag unloaded

– Jack up the motorcycle. ( p. 20) – Measure the distance – as vertical as possible – between the rear axle and a fixed

point, for example, a mark on the side cover.

– Make a note of the value as measurement . – Remove the motorcycle from the work stand. ( p. 20)

400220-10

Page 23

MAINTENANCE WORK ON CHASSIS AND ENGINE 21

000BB

9.5Checking the static sag of the shock absorber

– Measure distance  of rear wheel unloaded. ( p. 20) – Ask someone to help you by holding the motorcycle upright. – Measure the distance between the rear axle and the fixed point again. – Make a note of the value as measurement .

Info

The static sag is the difference between measurements  and .

– Check the static sag.

Static sag (50 SX) 20 mm (0.79 in)

Static sag (50 SX Mini) 15 mm (0.59 in)

» If the static sag is less or more than the specified value:

–

Adjust the spring preload of the shock absorber. x ( p. 21)

400221-10

9.6Checking the riding sag of the shock absorber

– Measure distance  of rear wheel unloaded. ( p. 20) – Hold the motorcycle in a vertical position and seat the rider, wearing a full set of

protective clothing, on the motorcycle in the normal sitting position (feet on the footrests). The rider should bounce up and down several times so that the rear wheel suspension can level out.

– Now measure the distance between the rear axle and the fixed point again. – Make a note of the value as measurement .

Info

The riding sag is the difference between measurements  and .

– Check the riding sag.

Riding sag (50 SX) 45… 55 mm (1.77… 2.17 in)

Riding sag (50 SX Mini) 40… 50 mm (1.57… 1.97 in)

» If the riding sag differs from the specified measurement:

–

Adjust the riding sag. x ( p. 22)

400222-10

9.7Adjusting the spring preload of the shock absorber x

Danger

Danger of accidents Disassembly of pressurized parts can lead to injury.

– The shock absorber is filled with high density nitrogen. Adhere to the description provided. (Your authorized KTM workshop

will be glad to help.)

–

Remove shock absorber. x ( p. 22)

– After removing the shock absorber, clean it thoroughly.

Page 24

MAINTENANCE WORK ON CHASSIS AND ENGINE 22

– Measure the full spring length while it is under tension and note down the value. – Loosen lock ring . – Turn adjusting ring  until the spring is no longer under tension.

Hook wrench (T106S)

– Measure the overall spring length when not under tension. – Tighten the spring by turning adjusting ring  to measurement.

Guideline

700506-01

Spring preload (50 SX)

Standard 3 mm (0.12 in)

Spring preload (50 SX Mini)

Standard 5 mm (0.2 in)

Info

Measure is the difference between the relaxed spring length and the tensioned spring length. Depending on the static sag and/or the riding sag, it may be necessary to increase or decrease the spring preload.

– Tighten lock ring .

–

Install shock absorber. x ( p. 23)

9.8Adjusting the riding sag x

–

Remove shock absorber. x ( p. 22)

– After removing the shock absorber, clean it thoroughly. – Choose and mount a suitable spring.

Guideline

Spring rate (50 SX)

Weight of rider: < 25 kg (< 55 lb.) 30 N/mm (171 lb/in) Weight of rider: 25… 35 kg (55… 77 lb.) 35 N/mm (200 lb/in) Weight of rider: > 40 kg (> 88 lb.) 40 N/mm (228 lb/in)

Spring rate (50 SX Mini)

Weight of rider: < 25 kg (< 55 lb.) 65 N/mm (371 lb/in) Weight of rider: 25… 35 kg (55… 77 lb.) 75 N/mm (428 lb/in) Weight of rider: > 35 kg (> 77 lb.) 85 N/mm (485 lb/in)

Info

The spring rate is shown on the outside of the spring. Smaller weight differences can be compensated by changing the spring preload.

–

Install shock absorber. x ( p. 23)

– Check the static sag of the shock absorber. ( p. 21) – Check the riding sag of the shock absorber. ( p. 21) – Adjust the rebound damping of the shock absorber. ( p. 20)

9.9Removing the shock absorber x

700477-01

– Jack up the motorcycle. ( p. 20) – Remove screw  and lower the rear wheel with the swing arm as far as possible

without blocking the rear wheel. Fix the rear wheel in this position.

– Remove screw , push splash protector  to the side, and remove the shock

absorber.

Page 25

MAINTENANCE WORK ON CHASSIS AND ENGINE 23

9.10Installing shock absorber x

– Push the splash protector  to the side and position the shock absorber according

to the desired seat height. Mount and tighten screw . Guideline

Screw, top shock absorber M10 45 Nm

(33.2 lbf ft)

– Mount and tighten screw .

Guideline

301060-10

9.11Vehicle level

Screw, bottom shock absorber M10 45 Nm

(33.2 lbf ft)

– Remove the motorcycle from the work stand. ( p. 20)

Warning

Danger of accidents Modifications to the suspension settings can seriously alter

the vehicle's ride behavior.

– Following modifications, ride slowly at first to get the feel of the new ride

behavior.

700523-10

700521-11

9.12Adjusting the fork overhang x

The vehicle level can be adjusted at the front by means of the clamping of the fork legs and at the rear by means of the positioning of the shock absorber.

The fork overhang can be individually adjusted to the size of the child. In the lower position  (standard), the fork is completely pushed through. In the higher position , the cone is flush with the upper triple clamp.

Fork overhang over the

10… 17 mm (0.39… 0.67 in)

upper triple clamp

The seat height can be individually adjusted to the size of the child. The shock absorber can be mounted at two different holes in the frame.

Difference between low 

25 mm (0.98 in) (standard) and high  seat position

Warning

Danger of accidents Modifications to the suspension settings can seriously alter the vehicle's ride behavior.

– Following modifications, ride slowly at first to get the feel of the new ride behavior.

– Loosen screws  on the lower triple clamp. – Loosen screw  on the upper triple clamp.

Info

Loosen the screws to the point where the fork legs can be moved without damaging it. Make the adjustments first on one fork leg and then on the other.

– Adjust the fork overhang with the upper triple clamp.

700524-01

Guideline

10… 17 mm (0.39… 0.67 in)

Page 26

MAINTENANCE WORK ON CHASSIS AND ENGINE 24

– Tighten screw .

Guideline

Screw, top triple clamp M8 25 Nm

(18.4 lbf ft)

– Fully tighten screws .

Guideline

Screw, bottom triple clamp M6 10 Nm (7.4 lbf ft)

– Repeat the adjustment on the other fork leg.

Info

The setting of the vehicle level via the fork legs must be identical on both fork legs.

9.13Adjusting seat height x

Warning

Danger of accidents Modifications to the suspension settings can seriously alter the vehicle's ride behavior.

– Following modifications, ride slowly at first to get the feel of the new ride behavior.

–

Remove shock absorber. x ( p. 22)

– Position the shock absorber according to the required seat height.

Guideline

Low seat position (standard)  High seat position 

700521-01

9.14Cleaning dust boots of fork legs

700478-11

–

Install shock absorber. x ( p. 23)

– Jack up the motorcycle. ( p. 20) – Push dust boots  of both fork legs upwards.

Info

The dust boots should remove dust and coarse dirt particles from the fork tubes. Over time, dirt can penetrate behind the dust boots. If this dirt is not removed, the oil seals behind can start to leak.

Warning

Danger of accidents Reduced braking efficiency due to oil or grease on the

brake discs.

– Always keep the brake discs free of oil and grease, and clean them with

brake cleaner when necessary.

– Clean and oil the dust boots and inner fork tube of both fork legs.

Universal oil spray ( p. 79)

– Press the dust boots back into their normal position. – Remove excess oil. – Remove the motorcycle from the work stand. ( p. 20)

Page 27

MAINTENANCE WORK ON CHASSIS AND ENGINE 25

9.15Checking play of steering head bearing

Warning

Danger of accidents Unstable vehicle handling from incorrect steering head bearing play.

– Adjust the steering head bearing play without delay. (Your authorized KTM workshop will be glad to help.)

Info

If the bike is ridden for a longer time with play in the steering head bearing, the bearing and the bearing seats in the frame can be damaged after time.

– Jack up the motorcycle. ( p. 20) – Move the handlebar to the straight-ahead position. Move the fork legs to and fro in

the direction of travel.

No play should be noticeable in the steering head bearing.

» If there is noticeable play:

–

Adjust play of the steering head bearing. x ( p. 25)

– Move the handlebar to and fro over the entire steering range.

The handlebar must move smoothly over the entire steering range. There should

400387-10

be no perceptible detent positions.

» If detent positions are noticeable:

–

Adjust play of the steering head bearing. x ( p. 25)

– Check the steering head bearing and replace if required.

– Remove the motorcycle from the work stand. ( p. 20)

9.16Adjusting play of steering head bearing x

– Jack up the motorcycle. ( p. 20)

– – Remove the fuel tank breather . – Remove screws . – Remove the handlebar clamp. – Remove the handlebar and lay it to one side.

300736-10

– Remove screws . – Take off the handlebar support.

300737-10

– Remove nut . – Take off the upper triple clamp.

Remove the fork legs. x ( p. 26)

Info

Protect the motorcycle and its attachments from damage by covering them. Do not bend the cables and lines.

300738-11

Page 28

MAINTENANCE WORK ON CHASSIS AND ENGINE 26

– Tighten nut .

Guideline

Steering head nut M20x1.5 10 Nm (7.4 lbf ft)

300739-10

– Position the upper triple clamp. – Mount nut , but do not tighten it yet.

Guideline

Nut, steering stem M20x1.5 10 Nm (7.4 lbf ft)

–

Install the fork legs. x ( p. 27)

– Tighten nut .

Guideline

300738-11

Nut, steering stem M20x1.5 10 Nm (7.4 lbf ft)

– Position the handlebar support. – Mount and tighten screws .

Guideline

Screw, handlebar support M10 40 Nm

Loctite®243™

(29.5 lbf ft)

9.17Removing the fork legs x

300742-11

300743-11

– Position the handlebar with the handlebar clamps. – Mount and tighten screws . – Position the fuel tank breather . – Check play of steering head bearing. ( p. 25) – Check the cable harness, bowden cables and brake line for freedom of movement

and routing.

– Remove the motorcycle from the work stand. ( p. 20)

–

Remove front wheel. x ( p. 45)

– Dismount the start number plate. ( p. 31) – Remove screws  and take off clamp.

300731-10

Page 29

MAINTENANCE WORK ON CHASSIS AND ENGINE 27

– Remove screws  with washers and brake caliper. – Hang the brake caliper and the brake line loosely to the side.

300732-10

– Loosen screw . Remove the left fork leg. – Loosen screw . Remove the right fork leg.

300733-10

9.18Installing the fork legs x

– Position the fork legs. – Adjust fork overhang .

Guideline

Upper fork projection 10… 17 mm (0.39… 0.67 in)

300734-10

300733-11

300732-11

– Tighten screw .

Guideline

Screw, top triple clamp M8 25 Nm

(18.4 lbf ft)

– Tighten screws .

Guideline

Screw, bottom triple clamp M6 10 Nm (7.4 lbf ft)

– Position the brake caliper, fit and tighten the screws  with washers.

Guideline

Screw, front brake caliper M8 20 Nm

Loctite®243™

(14.8 lbf ft)

– Position the brake line. Put the clamp on, and mount and tighten screws . – Install the start number plate. ( p. 31)

–

Install the front wheel. x ( p. 45)

300731-11

Page 30

MAINTENANCE WORK ON CHASSIS AND ENGINE 28

9.19Removing the lower triple clamp x

–

Remove the fork legs. x ( p. 26)

– Dismount the front fender. ( p. 30) – Remove the fuel tank breather . – Remove screws . – Remove the handlebar clamp. – Remove the handlebar and lay it to one side.

Info

Protect the motorcycle and its attachments from damage by covering them. Do not bend the cables and lines.

300736-10

– Remove screws . – Take off the handlebar support.

300737-10

300738-11

300739-10

– Remove nut . – Take off the upper triple clamp.

– Remove nut .

– Remove protector ring . – Remove the lower triple clamp with the steering stem. – Remove the upper steering head bearing.

300740-10

Page 31

MAINTENANCE WORK ON CHASSIS AND ENGINE 29

9.20Installing the lower triple clamp x

– Clean the bearing and sealing elements, check for damage, and grease.

Long-life grease ( p. 78)

– Insert the lower triple clamp with the steering stem. Mount the upper steering head

bearing.

Info

Check that the O-rings of the steering head seal are correctly positioned.

400563-01

– Push on protective ring . – Mount and tighten nut .

Guideline

Steering head nut M20x1.5 10 Nm (7.4 lbf ft)

300739-11

– Position the upper triple clamp. – Mount nut , but do not tighten it yet.

Guideline

Nut, steering stem M20x1.5 10 Nm (7.4 lbf ft)

300738-10

300741-10

– Position the fork leg. – Adjust fork overhang .

Guideline

Upper fork projection 10… 17 mm (0.39… 0.67 in)

– Tighten screw .

Guideline

Screw, top triple clamp M8 25 Nm

(18.4 lbf ft)

– Tighten screws .

Guideline

Screw, bottom triple clamp M6 10 Nm (7.4 lbf ft)

– Repeat these steps on the opposite side. – Tighten nut .

Guideline

Nut, steering stem M20x1.5 10 Nm (7.4 lbf ft)

– Position the handlebar support. – Mount and tighten screws .

Guideline

Screw, handlebar support M10 40 Nm

Loctite®243™

(29.5 lbf ft)

300742-10

Page 32

MAINTENANCE WORK ON CHASSIS AND ENGINE 30

– Position the handlebar with handlebar clamps. – Mount and tighten screws .

Guideline

Screw, handlebar clamp M8 20 Nm

(14.8 lbf ft)

– Position the fuel tank breather .

300743-10

– Position the brake caliper, fit and tighten the screws  with washers.

Guideline

300732-12

Screw, front brake caliper M8 20 Nm

(14.8 lbf ft)

– Position the brake line. Put the clamp on, and mount and tighten screws . – Install the front fender. ( p. 31) – Install the start number plate. ( p. 31)

–

Install the front wheel. x ( p. 45)

– Check that the wiring harness, Bowden cables and brake line have freedom of

movement and are routed correctly.

– Check play of steering head bearing. ( p. 25)

Loctite®243™

300731-12

9.21Greasing the steering head bearing x

400563-01

9.22Dismounting the front fender

–

Remove the lower triple clamp. x ( p. 28)

–

Install the lower triple clamp. x ( p. 29)

– Remove screws . Remove the front fender.

700479-10

Page 33

MAINTENANCE WORK ON CHASSIS AND ENGINE 31

9.23Installing the front fender

– Position the fender with holding lugs  into the drill holes on the start number

plate.

700480-01

– Position the front fender. Mount and tighten screws .

Guideline

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

700479-11

9.24Dismounting the start number plate

700466-01

9.25Installing the start number plate

700467-01

– Remove screw  and take off clamp. – Remove screw . Remove the start number plate.

– Position the start number plate with the drill holes onto the holding lugs  of the

fender.

– Mount and tighten screw .

Guideline

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

700468-01

– Position the brake line. Put the clamp on, mount and tighten screw .

Page 34

MAINTENANCE WORK ON CHASSIS AND ENGINE 32

000BB

0011

9.26Handlebar position

On the upper triple clamp, there are 2 holes at a distance of  to each other.

Distance  between holes 15 mm (0.59 in)

The holes on the handlebar support are placed at a distance of  from the center.

Distance  between holes 3.5 mm (0.138 in)

The handlebar supports can be mounted in 4 different positions.

400565-10

9.27Adjusting handlebar position x

Warning

Danger of accidents Handlebar breakage.

– If the handlebar is bent or straightened it will cause material fatigue, and the handlebar can break. Always replace handle-

bar.

– Remove the four screws . Remove the handlebar clamp. Remove the handlebar

and lay it to one side.

400564-10

9.28Checking the play in the throttle cable

Info

Protect the motorcycle and its attachments from damage by covering them. Do not bend the cables and lines.

– Remove the two screws . Remove the handlebar support. – Place the handlebar support in the required position. Mount and tighten the two

screws . Guideline

Screw, handlebar support M10 40 Nm

(29.5 lbf ft)

– Position the handlebar.

Info

Make sure cables and wiring are positioned correctly.

– Position the handlebar clamp. Mount and evenly tighten the four screws .

Guideline

Screw, handlebar clamp M8 20 Nm

Info

Make sure the gap width is even.

– Move the handlebar to the straight-ahead position. – Push back bellows . – Pull back the throttle cable casing until you sense a resistance. – Now check throttle cable play .

Loctite®243™

(14.8 lbf ft)

700481-10

Play in gas throttle cable 3… 5 mm (0.12… 0.2 in)

» If the throttle cable play does not meet specifications:

–

Adjust the play in the throttle cable. x ( p. 33)

– Push on bellows . Check the throttle grip for smooth operation.

Page 35

MAINTENANCE WORK ON CHASSIS AND ENGINE 33

9.29Adjusting the play in the throttle cable x

– Move the handlebar to the straight-ahead position. – Push back bellows . – Loosen nut . Turn adjusting screw  in as far as possible. – Turn the adjusting screw so that there is play  at the outer casing of the throttle

cable. Guideline

Play in gas throttle cable 3… 5 mm (0.12… 0.2 in)

700481-11

9.30Checking chain dirt

– Tighten the nut. – Push on bellows . Check the throttle grip for smooth operation.

– Check the chain for coarse dirt accumulation.

» If the chain is very dirty:

– Clean the chain. ( p. 33)

400678-01

9.31Cleaning the chain

Warning

Danger of accidents Oil or grease on the tires reduces their grip.

– Remove oil and grease with a suitable cleaning material.

Warning

Danger of accidents Reduced braking efficiency due to oil or grease on the brake discs.

– Always keep the brake discs free of oil and grease, and clean them with brake cleaner when necessary.

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

The service life of the chain depends largely on its maintenance.

– Clean the chain regularly and then treat with chain spray.

Chain cleaner ( p. 78) Offroad chain spray ( p. 78)

400725-01

Page 36

MAINTENANCE WORK ON CHASSIS AND ENGINE 34

9.32Checking the chain tension

Warning

Danger of accidents Danger caused by incorrect chain tension.

– If the chain is over tensioned, the components of the secondary power train (chain, engine sprocket, rear sprocket, bear-

ings in transmission and rear wheel) are under additional load. Apart from premature wear, in extreme cases the chain may snap or the countershaft of the transmission can break. On the other hand, if the chain is loose, it may jump off the engine sprocket or the rear sprocket, causing the rear wheel to lock or damage the engine. Check for correct chain tension and adjust if necessary.

– Jack up the motorcycle. ( p. 20) – Push the chain at the end of the chain sliding component upward to measure the

chain tension .

Info

The upper chain section  must be taut. Because chain wear is not always even, repeat this measurement at different chain positions.

Chain tension 5… 8 mm (0.2… 0.31 in)

700483-01

» If the chain tension does not meet specifications:

– Adjusting chain tension - after checking. ( p. 35)

– Remove the motorcycle from the work stand. ( p. 20)

9.33Checking the chain tension - installing rear wheel

Warning

Danger of accidents Danger caused by incorrect chain tension.

– If the chain is over tensioned, the components of the secondary power train (chain, engine sprocket, rear sprocket, bear-

– Make sure that the chain adjuster support plates are lying on the adjusting screws. – Push the chain at the end of the chain sliding component upward to measure the

chain tension .

Info

The upper chain section  must be taut. Because chain wear is not always even, repeat this measurement at different chain positions.

700483-01

9.34Checking rear sprocket / engine sprocket for wear

Chain tension 5… 8 mm (0.2… 0.31 in)

» If the chain tension does not meet specifications:

– Adjust the chain tension when installing the rear wheel. ( p. 36)

– Check rear sprocket / engine sprocket for wear.

» If the rear sprocket / engine sprocket are worn:

– Replace rear sprocket / engine sprocket.

400227-01

Info

When fitting the chain joint, always make sure that the closed side of the joint faces forward (riding direction). The engine sprocket, rear sprocket and chain should always be replaced together.

– Check the chain guide for tightness and wear.

Page 37

MAINTENANCE WORK ON CHASSIS AND ENGINE 35

9.35Adjusting chain tension

Warning

Danger of accidents Danger caused by incorrect chain tension.

– If the chain is over tensioned, the components of the secondary power train (chain, engine sprocket, rear sprocket, bear-

– Jack up the motorcycle. ( p. 20) – Push the chain at the end of the chain sliding component upward to measure the

chain tension .

Info

The upper chain section  must be taut. Because chain wear is not always even, repeat this measurement at different chain positions.

700483-01

– Loosen nut . – Adjust the chain tension by turning the adjusting screws  left and right.

Guideline

Chain tension 5… 8 mm (0.2… 0.31 in) Turn adjusting screws  equally on the left and right. Check that the rear wheel

is aligned with the front wheel.

700484-11

9.36Adjusting chain tension - after checking

700484-10

– Make sure that the chain adjuster supports  are fitted correctly on the adjusting

screws .

– Tighten nut .

Guideline

Nut, rear wheel spindle M12x1 40 Nm

(29.5 lbf ft)

– Remove the motorcycle from the work stand. ( p. 20)

– Loosen nut . – Adjust the chain tension by turning the adjusting screws  left and right.

Guideline

Chain tension 5… 8 mm (0.2… 0.31 in) Turn adjusting screws  equally on the left and right. Check that the rear wheel

is aligned with the front wheel.

– Make sure that the chain adjuster supports  are fitted correctly on the adjusting

screws .

– Tighten nut .

Guideline

Nut, rear wheel spindle M12x1 40 Nm

(29.5 lbf ft)

Page 38

MAINTENANCE WORK ON CHASSIS AND ENGINE 36

9.37Adjusting chain tension - installing rear wheel

– Adjust the chain tension by turning the adjusting screws  left and right.

Guideline

Chain tension 5… 8 mm (0.2… 0.31 in) Turn adjusting screws  equally on the left and right. Check that the rear wheel

is aligned with the front wheel.

700484-12

9.38Adjusting the chain guide x

Info

The size of the chain wheel varies with the number of teeth. The chain guide can be adjusted on small sprockets.

– Loosen screw . – Position the chain guide. – Tighten screw.

Guideline

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

700485-01

9.39Checking brake discs

Warning

Danger of accidents Reduced braking efficiency due to worn brake disc(s).

– Change the worn brake disc(s) without delay. (Your authorized KTM workshop will be glad to help.)

– Check the thickness of the front and rear brake discs at several places on the disc

to see if it conforms to measurement .

Info

Wear reduces the thickness of the brake disc around the area used by the brake linings.

Brake discs - wear limits

Front 2.2 mm (0.087 in)

400257-10

– Check the front and rear brake discs for damage, cracking and deformation.

Rear 2.2 mm (0.087 in)

» If the brake disc thickness is less than the specified value:

– Change the brake disc.

» If the brake disk exhibits damage, cracking or deformation:

– Change the brake disc.

Page 39

MAINTENANCE WORK ON CHASSIS AND ENGINE 37

9.40Checking play of handbrake lever

– Push the handbrake lever forwards and check the play .

Play at handbrake lever 3… 5 mm (0.12… 0.2 in)

» If the play does not meet specifications:

– Adjust the play of the handbrake lever. ( p. 37)

700486-01

9.41Adjusting play of handbrake lever

– Check the play of the handbrake lever. ( p. 37) – Adjust the play of the handbrake lever with the adjusting screw .

Guideline

Play at handbrake lever 3… 5 mm (0.12… 0.2 in)

700487-01

9.42Adjusting basic position of handbrake lever

– Check the play of the handbrake lever. ( p. 37) – Adjust the basic position of the handbrake lever with the adjusting screw  to the

rider's hand size.

Info

Turn the adjusting screw clockwise to increase the distance between the handbrake lever and the handlebar. Turn the adjusting screw counterclockwise to decrease the distance between the handbrake lever and the handlebar.

700528-01

9.43Checking the front brake fluid level

The range of adjustment is limited.

Warning

Danger of accidents Brake system failure.

– If the brake fluid level drops below the specified marking or the specified value, this is an indication that the brake system

is leaking or that the brake linings are completely worn down. Check the brake system and do not continue riding. (Your authorized KTM workshop will be glad to help.)

Warning

Skin irritation Brake fluid can cause skin irritation on contact.

– Avoid contact with skin and eyes, and keep out of the reach of children. – Wear suitable protective clothing and goggles. – If brake fluid gets into your eyes, rinse thoroughly with water and contact a doctor immediately.

Warning

Danger of accidents Reduced braking efficiency due to old brake fluid.

– Change the brake fluid of the front and rear brakes according to the service schedule. (Your authorized KTM workshop will

be glad to help.)

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Page 40

MAINTENANCE WORK ON CHASSIS AND ENGINE 38

Info

Never user DOT 5 brake fluid! This is based on silicone oil and is colored purple. Oil seals and brake lines are not designed for DOT 5 brake fluid. Avoid contact between brake fluid and painted parts. Brake fluid attacks paint! Use only clean brake fluid from a sealed container!

– Move the brake fluid reservoir mounted on the handlebar to a horizontal position. – Remove screws . – Remove cover  with diaphragm . – Check the brake fluid level.

301061-10

Brake fluid level under top level of container

» If the brake fluid level does not meet specifications:

–

Add front brake fluid. x ( p. 38)

– Position the cover with the diaphragm. Mount and tighten the screws.

5 mm (0.2 in)

Info

Clean up overflowed or spilt brake fluid immediately with water.

9.44Adding front brake fluid x

Warning

Danger of accidents Brake system failure.

– If the brake fluid level drops below the specified marking or the specified value, this is an indication that the brake system

is leaking or that the brake linings are completely worn down. Check the brake system and do not continue riding. (Your authorized KTM workshop will be glad to help.)

Warning

Skin irritation Brake fluid can cause skin irritation on contact.

Warning

Danger of accidents Reduced braking efficiency due to old brake fluid.

– Change the brake fluid of the front and rear brakes according to the service schedule. (Your authorized KTM workshop will

be glad to help.)

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

– Move the brake fluid reservoir mounted on the handlebar to a horizontal position. – Remove screws . – Remove cover  with diaphragm . – Correct the brake fluid level.

Guideline

301061-10

Brake fluid level under top level of container

Brake fluid DOT 4 / DOT 5.1 ( p. 76)

5 mm (0.2 in)

Page 41

MAINTENANCE WORK ON CHASSIS AND ENGINE 39

– Position the cover with the diaphragm. Mount and tighten the screws.

Info

Clean up overflowed or spilt brake fluid immediately with water.

9.45Checking the front brake linings

Warning

Danger of accidents Reduced braking efficiency caused by worn brake linings.

– Change worn brake linings immediately. (Your authorized KTM workshop will be glad to help.)

– Check the brake linings for minimum thickness .

Minimum thickness  ≥ 1 mm (≥ 0.04 in)

» If the minimum thickness is less than specified:

–

Change the front brake linings. x ( p. 40)

– Check the brake linings for damage and cracking.

» If damage or wear is encountered:

–

Change the front brake linings. x ( p. 40)

700498-01

9.46Removing front brake linings x

Warning

Danger of accident Brake system failure.

– Maintenance work and repairs must be carried out professionally. (Your authorized KTM workshop will be glad to help.)

–

Remove front wheel. x ( p. 45)

– Remove the lock washer . – Remove screw .

700499-01

– Remove the brake linings. – Clean brake caliper and brake caliper support.

700500-01

9.47Installing the front brake linings x

Warning

Danger of accidents Reduced braking efficiency due to oil or grease on the brake discs.

– Always keep the brake discs free of oil and grease, and clean them with brake cleaner when necessary.

Page 42

MAINTENANCE WORK ON CHASSIS AND ENGINE 40

Warning

Danger of accidents Reduced braking efficiency due to use of non-approved brake linings.

– Brake linings available from accessory suppliers are often not tested and approved for use on KTM vehicles. The construc-

tion and friction factor of the brake linings and therefore the brake power can differ considerably from the original KTM brake linings. If brake linings are used that differ from the originals, there is no guarantee that they comply with the original license. The vehicle no longer corresponds to the condition at delivery, and the warranty is no longer valid.

– Check the brake discs. ( p. 36) – Insert the brake linings.

Info

Ensure that the brake linings are correctly positioned in the holding spring.

700500-01

– Mount screw . – Fit the lock washer .

–

Install the front wheel. x ( p. 45)

700501-01

9.48Changing the front brake linings x

Warning

Skin irritation Brake fluid can cause skin irritation on contact.

Warning

Danger of accidents Reduced braking efficiency due to old brake fluid.

– Change the brake fluid of the front and rear brakes according to the service schedule. (Your authorized KTM workshop will

be glad to help.)

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

–

Remove the front brake linings. x ( p. 39)

Page 43

MAINTENANCE WORK ON CHASSIS AND ENGINE 41

– Move the brake fluid reservoir mounted on the handlebar to a horizontal position. – Remove screws . – Remove cover  with diaphragm . – Press the brake piston back to its basic position and make sure that no brake fluid

overflows from the brake fluid reservoir.

–

Install the front brake linings. x ( p. 39)

– Correct the brake fluid level.

301061-10

9.49Checking the free travel of the foot brake lever

Warning

Danger of accidents Brake system failure.

– If there is no free travel on the foot brake pedal, pressure builds up on the rear brake in the brake system. The rear brake

can fail due to overheating. Adjust free travel on foot brake pedal according to specifications.

Guideline

Brake fluid level under top level of con-

5 mm (0.2 in)

tainer

Brake fluid DOT 4 / DOT 5.1 ( p. 76)

– Position the cover with the diaphragm. Mount and tighten the screws.

Info

Clean up overflowed or spilt brake fluid immediately with water.

– Disconnect spring . – Move the foot brake lever backwards and forwards between the end stop and the

foot brake cylinder piston bracket and check free travel . Guideline

Free play at foot brake lever 3… 5 mm (0.12… 0.2 in)

» If the free travel does not meet specifications:

–

Adjust the free travel of the foot brake pedal. x

700488-01

9.50Adjusting basic position of foot brake pedal x

– Attach spring .

Warning

Danger of accidents Brake system failure.

– If there is no free travel on the foot brake pedal, pressure builds up on the rear brake in the brake system. The rear brake

can fail due to overheating. Adjust free travel on foot brake pedal according to specifications.

– Detach the spring. – Loosen nut . – Turn back push rod  until free travel is at a maximum. – For an individual adjustment of the basic position of the footbrake pedal, loose the

screw  and turn the eccentric brake lever stop  accordingly.

– Tighten screw .

Guideline

700489-01

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

– Turn push rod  until clearance  is created.

Guideline

Free play at foot brake lever 3… 5 mm (0.12… 0.2 in)

– Hold push rod  and tighten nut . – Attach the spring. – Check whether the basic position of the foot brake pedal is suitable for the rider.

Page 44

MAINTENANCE WORK ON CHASSIS AND ENGINE 42

9.51Checking rear brake fluid level

Warning

Danger of accidents Failure of the brake system.

– If the brake fluid level falls below the MIN mark, this indicates a leakage in the brake system or worn-out brake linings.

Check the brake system and do not continue riding. (Your authorized KTM workshop will be glad to help.)

Warning

Danger of accidents Reduced braking efficiency due to old brake fluid.

– Change the brake fluid of the front and rear brakes according to the service schedule. (Your authorized KTM workshop will

be glad to help.)

– Stand the vehicle upright. – Check the brake fluid level in the viewer .

» When an air bubble is visible in the viewer :

–

Add rear brake fluid. x ( p. 42)

700490-01

9.52Adding rear brake fluid x

Warning

Danger of accidents Failure of the brake system.

– If the brake fluid level falls below the MIN mark, this indicates a leakage in the brake system or worn-out brake linings.

Check the brake system and do not continue riding. (Your authorized KTM workshop will be glad to help.)

Warning

Skin irritation Brake fluid can cause skin irritation on contact.

Warning

Danger of accidents Reduced braking efficiency due to old brake fluid.

– Change the brake fluid of the front and rear brakes according to the service schedule. (Your authorized KTM workshop will

be glad to help.)

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

201175-10

– Jack up the motorcycle. ( p. 20) – Remove screws . – Take off cover  with washer  and membrane .

Page 45

MAINTENANCE WORK ON CHASSIS AND ENGINE 43

– Add brake fluid to level .

Guideline

Dimension  (brake fluid level below top edge of container)

Brake fluid DOT 4 / DOT 5.1 ( p. 76)

– Position the membrane and the cover with the washer. Mount and tighten the

screws.

10 mm (0.39 in)

201170-10

Info

Clean up overflowed or spilt brake fluid immediately with water.

9.53Checking the rear brake linings

Warning

Danger of accidents Reduced braking efficiency caused by worn brake linings.

– Change worn brake linings immediately. (Your authorized KTM workshop will be glad to help.)

– Check the brake linings for minimum thickness .

Minimum thickness  ≥ 1 mm (≥ 0.04 in)

» If the minimum thickness is less than specified:

–

Change the rear brake linings. x ( p. 44)

– Check the brake linings for damage and cracking.

» If damage or wear is encountered:

–

Change the rear brake linings. x ( p. 44)

700491-01

9.54Removing rear brake linings x

Warning

Danger of accident Brake system failure.

– Maintenance work and repairs must be carried out professionally. (Your authorized KTM workshop will be glad to help.)

700492-01

700493-01

–

Remove the rear wheel. x ( p. 46)

– Remove the lock washer . – Remove screw .

– Remove the brake linings. – Clean brake caliper and brake caliper support.

Page 46

MAINTENANCE WORK ON CHASSIS AND ENGINE 44

9.55Installing the rear brake linings x

Warning

Danger of accidents Reduced braking efficiency due to oil or grease on the brake discs.

– Always keep the brake discs free of oil and grease, and clean them with brake cleaner when necessary.

Warning

Danger of accidents Reduced braking efficiency due to use of non-approved brake linings.

– Brake linings available from accessory suppliers are often not tested and approved for use on KTM vehicles. The construc-

– Check the brake discs. ( p. 36) – Insert the brake linings.

Info

Ensure that the brake linings are correctly positioned in the holding spring.

700493-10

– Mount screw . – Fit the lock washer .

–

Install the rear wheel. x ( p. 46)

700494-01

9.56Changing the rear brake linings x

Warning

Skin irritation Brake fluid can cause skin irritation on contact.

Warning

Danger of accidents Reduced braking efficiency due to old brake fluid.

– Change the brake fluid of the front and rear brakes according to the service schedule. (Your authorized KTM workshop will

be glad to help.)

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

Page 47

MAINTENANCE WORK ON CHASSIS AND ENGINE 45

–

Remove the rear brake linings. x ( p. 43)

– Remove screws . – Take off cover  with washer  and membrane . – Press the brake piston back to its basic position and make sure that no brake fluid

overflows from the brake fluid reservoir.

–

Install the rear brake linings. x ( p. 44)

201175-10

– Add brake fluid to level .

Guideline

Dimension  (brake fluid level below top edge of container)

Brake fluid DOT 4 / DOT 5.1 ( p. 76)

– Position the membrane and the cover with the washer. Mount and tighten the

screws.

10 mm (0.39 in)

9.57Removing front wheel x

201170-10

700502-01

Info

Clean up overflowed or spilt brake fluid immediately with water.

– Jack up the motorcycle. ( p. 20) – Remove nut  with washer.

– Hold the front wheel and pull out the wheel spindle  with the washer . Take the

front wheel out of the fork.

Info

Do not pull the hand brake lever when the front wheel is removed. Always lay the wheel down in such a way that the brake disc is not damaged.

700503-01

9.58Installing the front wheel x

Warning

Danger of accidents Reduced braking efficiency due to oil or grease on the brake discs.

– Always keep the brake discs free of oil and grease, and clean them with brake cleaner when necessary.

– Clean and grease wheel spindle .

Long-life grease ( p. 78)

Page 48

MAINTENANCE WORK ON CHASSIS AND ENGINE 46

– Lift the front wheel into the fork, position it, and insert wheel spindle  with

washer .

700503-10

– Position washer . – Mount and tighten nut .

Guideline

Front wheel spindle nut M12x1 40 Nm

(29.5 lbf ft)

– Remove the motorcycle from the work stand. ( p. 20) – Operate the hand brake lever several times until the brake pads are lying correctly

700502-10

9.59Removing rear wheel x

on the brake disc.

– Jack up the motorcycle. ( p. 20) – Remove nut . – Remove the washer . – Pull out the wheel spindle  with the washer . – Remove the chain from the rear sprocket. – Take the rear wheel out of the swing arm.

Info

Do not operate the foot brake when the rear wheel is removed.

700495-01

9.60Installing the rear wheel x

Always lay the wheel down in such a way that the brake disc is not damaged.

Warning

Danger of accidents Reduced braking efficiency due to oil or grease on the brake discs.

– Always keep the brake discs free of oil and grease, and clean them with brake cleaner when necessary.

– Clean and grease wheel spindle .

Long-life grease ( p. 78)

– Lift the rear wheel into the swingarm and place the chain on the rear sprocket. – Insert the wheel spindle  with the washer . – Position washer . Mount nut , but do not tighten it yet. – Check chain tension when installing the rear wheel. ( p. 34) – Make sure that the chain adjuster supports are fitted correctly on the adjusting

screws.

– Tighten nut .

Guideline

700496-01

Nut, rear wheel spindle M12x1 40 Nm

(29.5 lbf ft)

– Operate the foot brake lever repeatedly until the brake linings lie on the brake disc

and there is a tight spot.

– Remove the motorcycle from the work stand. ( p. 20)

Page 49

MAINTENANCE WORK ON CHASSIS AND ENGINE 47

9.61Checking the tire condition

Info

Only mount tires that have been approved and/or recommended by KTM. Other tires could have a negative effect on vehicle handling. The type, condition and air pressure of the tires all have an important impact on the handling characteristics of the motorcycle. The tires mounted on the front and rear wheels must have the same profile. Worn tires have a negative effect on vehicle handling, especially on wet surfaces.

– Check the front and rear tires for cuts, run-in objects and other damage.

» If the tires exhibit cuts, run-in objects or other damage:

– Change the tires.

– Check the depth of the tread.

Info

Note local national regulations concerning the minimum tread depth.

400602-10

Minimum tread depth ≥ 2 mm (≥ 0.08 in)

» If the tread depth is less than the minimum permissible depth:

– Change the tires.

– Check the tire age.

Info

The tire's date of manufacture is usually part of the tire markings and is indicated by the last four digits of the DOT marking. The first two digits refer to the week of manufacture and last two digits refer to the year of manufacture. KTM recommends that the tires be changed regardless of the actual wear, at the latest after 5 years.

» If a tire is more than 5 years old:

– Change the tires.

9.62Checking tire air pressure

Info

Low tire air pressure leads to abnormal wear and overheating of the tire. Correct tire air pressure ensures optimal riding comfort and maximum tire service life.

– Remove the dust cap. – Check the tire air pressure when the tires are cold.

Tire air pressure off road

Front 1.0 bar (15 psi) Rear 1.0 bar (15 psi)

» If the tire pressure does not meet specifications:

– Correct the tire pressure.

400695-01

9.63Checking spoke tension

– Mount the dust cap.

Warning

Danger of accidents Instable handling due to incorrect spoke tension.

– Ensure that the spoke tension is correct. (Your authorized KTM workshop will be glad to help.)

Info

A loose spoke can cause wheel imbalance, which leads to more loose spokes in a short time. If the spokes are too tight, they can break due to local overload. Check the spoke tension regularly, especially on a new motorcycle.

Page 50

MAINTENANCE WORK ON CHASSIS AND ENGINE 48

– Briefly strike each spoke with the blade of a screwdriver.

Info

The frequency of the tone depends on the spoke length and diameter. If you hear different tone frequencies from spokes of the same length and thickness, this is an indication that the spoke tension differs.

You should hear a high note.

9.64Removing the seat

9.65Mounting the seat

400694-01

300611-10

» If the spoke tension differs:

–

Correct the spoke tension. x

– Check the spoke torque.

Guideline

Spoke nipple M3.5 3 Nm (2.2 lbf ft)

Torque wrench with various accessories in set (58429094000)

– Open quick release  and raise the rear of the seat. – Pull back the seat and remove it.

– Hook the seat onto screw  and lower the seat at the rear while pushing it forward.

Projection  hooks into the fuel tank.

9.66Cooling system

300612-10

– Close quick release .

300611-11

The water pump  in the engine forces the coolant to flow. The pressure resulting from the warming of the cooling system is regulated by a valve in the radiator cap . The specified coolant temperature is therefore permissible without danger of function problems.

120 °C (248 °F)

Cooling is effected by the air stream. The lower the speed, the less the cooling effect. Dirty cooling fins also reduce the cooling effect.

700509-01

Page 51

MAINTENANCE WORK ON CHASSIS AND ENGINE 49

9.67Checking the antifreeze and coolant level

Warning

Danger of scalding During motorcycle operation, the coolant gets very hot and is under pressure.

– Do not open the radiator, radiator hoses or other cooling system components when the engine is hot. Allow the engine and

cooling system to cool down. In case of burns, rinse immediately with lukewarm water.

Warning

Danger of poisoning Coolants are poisonous and a health hazard.

– Avoid contact between coolants and skin, eyes and clothing. If fuel gets into your eyes, rinse immediately with water and

contact a doctor. Wash affected skin areas immediately with soap and water. If coolant is swallowed, contact a doctor immediately. Change clothes that have come into contact with coolants. Keep coolants out of the reach of children.

Info

Carry out this work with a cold engine.

– Stand the motorcycle upright on a horizontal surface. – Remove radiator cap . – Check the antifreeze of the coolant.

−25… −45 °C (−13… −49 °F)

» If the antifreeze of the coolant does not meet specifications:

– Correct the antifreeze of the coolant.

700510-01

– Check the coolant level in the radiator.

Coolant level  above the radiator fins 10 mm (0.39 in)

» If the coolant level does not meet specifications:

– Correct the coolant level.

Alternative 1

Coolant ( p. 76)

Alternative 2

400243-10

Coolant (mixed ready to use) ( p. 76)

– Mount the radiator cap.

9.68Checking the coolant level

Warning

Danger of scalding During motorcycle operation, the coolant gets very hot and is under pressure.

– Do not open the radiator, radiator hoses or other cooling system components when the engine is hot. Allow the engine and

cooling system to cool down. In case of burns, rinse immediately with lukewarm water.

Warning

Danger of poisoning Coolants are poisonous and a health hazard.

– Avoid contact between coolants and skin, eyes and clothing. If fuel gets into your eyes, rinse immediately with water and

Info

Carry out this work with a cold engine.

Page 52

MAINTENANCE WORK ON CHASSIS AND ENGINE 50

– Stand the motorcycle upright on a horizontal surface. – Remove the radiator cap. – Check the coolant level in the radiator.

Coolant level  above the radiator fins 10 mm (0.39 in)

» If the coolant level does not meet specifications:

– Correct the coolant level.

Alternative 1

400243-10

– Mount the radiator cap.

9.69Draining the coolant x

Warning

Danger of scalding During motorcycle operation, the coolant gets very hot and is under pressure.

– Do not open the radiator, radiator hoses or other cooling system components when the engine is hot. Allow the engine and

cooling system to cool down. In case of burns, rinse immediately with lukewarm water.

Warning

Danger of poisoning Coolants are poisonous and a health hazard.

– Avoid contact between coolants and skin, eyes and clothing. If fuel gets into your eyes, rinse immediately with water and

Coolant ( p. 76)

Alternative 2

Coolant (mixed ready to use) ( p. 76)

Info

Carry out this work with a cold engine.

– Stand the vehicle upright. – Place a suitable container under the engine. – Remove screw . Remover the radiator cap. – Completely drain the coolant. – Mount and tighten screw  with a new seal ring.

Guideline

Screw, water pump cover M6 10 Nm (7.4 lbf ft)

300617-10

9.70Refilling coolant x

Warning

Danger of poisoning Coolants are poisonous and a health hazard.

– Avoid contact between coolants and skin, eyes and clothing. If fuel gets into your eyes, rinse immediately with water and

– Make sure that the screw  is tightened. – Stand the vehicle upright. – Add coolant to level .

Guideline

Level  above the radiator fins 10 mm (0.39 in)

700511-01

Coolant 0.5 l (0.5 qt.) Coolant ( p. 76)

Coolant (mixed ready to use) ( p. 76)

Page 53

MAINTENANCE WORK ON CHASSIS AND ENGINE 51

00AA00

– Position the vehicle as shown and secure it against rolling away. A height differ-

ence of  must be reached. Guideline

Height difference  100 cm (39.4 in)

Info

To ensure that all of the air can escape from the cooling system, the front of the vehicle must be jacked up. A poorly bled cooling system is less effective

400677-11

– Place the vehicle back on a level surface. – Add coolant to level . – Mount the radiator cap. – Make a short test ride. – Check the coolant level. ( p. 49)

9.71Removing main silencer

Warning

Danger of burns The exhaust system gets very hot when the vehicle is driven.

– Allow the exhaust system to cool down. Do not touch hot components.

at cooling and may result in overheating of the engine.

9.72Installing the main silencer

– Remove screw . – Remove screw .

700512-01

– Pull the main silencer off of the manifold at the rubber sleeve .

700513-10

– Position the main silencer. – Mount the main silencer with the rubber sleeve . – Mount the silentblock with the screw .

Guideline

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

700513-01

Page 54

MAINTENANCE WORK ON CHASSIS AND ENGINE 52

– Position the collar sleeves. – Mount and tighten screw .

Guideline

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

700512-10

9.73Glass fiber yarn filling of main silencer

The main silencer is filled with glass fiber yarn. Over a period, the fibers of the insulating material vanish into the air, and the silencer "burns out". Not only is the noise level higher, the performance characteristic changes.

9.74Removing the glass fiber yarn filling of the main silencer x

Warning

Danger of burns The exhaust system gets very hot when the vehicle is driven.

– Allow the exhaust system to cool down. Do not touch hot components.

– Remove the main silencer. ( p. 51) – Remove screws  of locking cap . Remove locking cap and outer tube . – Pull the glass fiber yarn filling  from the inner tube. – Clean the parts that are to be reinstalled.

700514-01

9.75Installing the glass fiber yarn filling of the main silencer x

– Slide the glass fiber yarn filling  over the inner tube. – Slide the outer tube  over the glass fiber yarn filling. – Insert the locking cap  into the outer tube. Fit and tighten screws  with tooth

lock washer. Guideline

Remaining screws, chassis M6 10 Nm (7.4 lbf ft)

– Install the main silencer. ( p. 51)

700514-10

9.76Removing the air filter x

Note

Engine failure Unfiltered intake air has a negative effect on the service life of the engine.

– Never ride the vehicle without an air filter since dust and dirt can get into the engine and result in increased wear.

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

– Remove the seat. ( p. 48)

Page 55

MAINTENANCE WORK ON CHASSIS AND ENGINE 53

– Press the rear holding lugs  together slightly and swing the air filer cover upward.

Pull out the front holding lug and take off the air filter cover.

– Take off the air filter.

700504-01

9.77Installing the air filter x

– Position the clean air filter. – Position the rear holding lug. Lower the air filter cover and allow the front holding

lug  to snap in.

Info

If the air filter is not correctly mounted, dust and dirt can penetrate into the engine and can cause damage.

– Mount the seat. ( p. 48)

700505-01

9.78Cleaning air filter x

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

Do not clean the air filter with fuel or petroleum since these substances attack the foam.

–

Remove the air filter. x ( p. 52)

– Wash the air filter thoroughly in special cleaning liquid and allow it to dry properly.

Air filter cleaner ( p. 78)

Info

Only press the air filter to dry it, never wring it out.

– Oil the dry air filter with a high/quality filter oil.

Oil for foam air filter ( p. 78)

– Clean the air filter box. – Check carburetor connection boot for damage and tightness.

–

Install the air filter. x ( p. 53)

9.79Carburetor - idle (50 SX)

700520-01

The idle setting of the carburetor has a big influence on the starting behavior, stable idling and the response to throttle opening. That means that an engine with a correctly set idle speed is easier to start than if the idle is set wrongly.

Info

The carburetor and its components are subject to increased wear caused by engine vibration. Wear can result in malfunctioning.

The idle speed is adjusted with the idle adjustment screw . The idle mixture is adjusted with the idle mixture adjustment screw .

Page 56

MAINTENANCE WORK ON CHASSIS AND ENGINE 54

9.80Carburetor - idle (50 SX Mini)

Info

The carburetor and its components are subject to increased wear caused by engine vibration. Wear can result in malfunctioning.

700522-01

9.81Carburetor - adjusting idle speed x (50 SX)

The idle speed is adjusted with the adjustment screw . The idle mixture is adjusted with the idle mixture adjustment screw .

– Screw in the idle adjusting screw  until it stops and then to the prescribed basic

– Run the engine until warm.

700520-01

– Adjust the idle speed with the adjusting screw .

setting. Guideline

Idle mixture adjusting screw

Open 3 turns

Guideline

Warm-up time ≥ 5 min

Danger

Danger of poisoning Exhaust gases are poisonous and can result in uncon-

sciousness and/or death.

– When running the engine, always make sure there is sufficient venti-

lation, and do not start or run the engine in a closed space without an effective exhaust extraction system.

Guideline

Choke function deactivated – Choke knob is in lower position. No O-ring is visible. ( p. 11)

Idle speed 1,400… 1,500 rpm

– Turn the idle adjusting screw  slowly clockwise until the idle speed begins to fall. – Note the position and turn the idle adjusting screw slowly counterclockwise until

the idle speed falls.

– Adjust to the point between these two positions with the highest idle speed.

Info

If the speed rise is too high, reduce the idle speed to a normal level and repeat the preceding steps. If the procedure described here does not lead to satisfactory results, the cause may be a wrongly dimensioned idling jet. If you can turn the idle adjusting screw to the end without any change of engine speed, you have to install a smaller idling jet. After changing the idling jet, start from the beginning with the adjusting steps. Following extreme air temperature or altitude changes, adjust the idle speed again.

Page 57

MAINTENANCE WORK ON CHASSIS AND ENGINE 55

9.82Carburetor - adjusting idle speed x (50 SX Mini)

– Screw in idle air adjusting screw  all the way and turn it to the specified basic

position. Guideline

Idle air adjusting screw

Open 1 turn

– Run the engine until warm.

Guideline

700522-01

Warm-up time ≥ 5 min

Danger

Danger of poisoning Exhaust gases are poisonous and can result in uncon-

sciousness and/or death.

– When running the engine, always make sure there is sufficient venti-

lation, and do not start or run the engine in a closed space without an effective exhaust extraction system.

– Adjust the idle speed with the adjusting screw .

Guideline

Choke function deactivated – The choke lever is pushed down all the way.

( p. 11)

Idle speed 1,400… 1,500 rpm

9.83Checking oil level (50 SX Mini)

– Turn idle air adjusting screw  slowly in a clockwise direction until the idle speed

begins to fall.

– Note the position and turn the idle air adjusting screw slowly counterclockwise until

the idle speed falls again.

– Adjust to the point between these two positions with the highest idle speed.

Info

If the speed rise is too high, reduce the idle speed to a normal level and repeat the preceding steps. If the procedure described here does not lead to satisfactory results, the cause may be a wrongly dimensioned idling jet. If you can turn the idle air adjusting screw to the end without any change of engine speed, you need to install a smaller idling jet. After changing the idling jet, start from the beginning with the adjusting steps. Following extreme air temperature or altitude changes, adjust the idle speed again.

– Stand the motorcycle upright on a horizontal surface. – Check the oil level in the oil tank.

For a full fuel tank, the oil tank must be filled up to MIN mark  at a minimum.

» If the oil level does not meet specifications:

– Fill up with oil. ( p. 17)

700518-01

Page 58

MAINTENANCE WORK ON CHASSIS AND ENGINE 56

9.84Bleeding oil pump x (50 SX Mini)

Condition

Fuel tank removed. – Pull off the oil line .

300650-10

– Fill the oil line with a syringe.

2-stroke engine oil ( p. 76)

300652-10

300650-10

300651-10

– Connect the oil line .

– Remove screws . – Take off the oil pump. – Pull off the oil line  from the carburetor.

– Turn the oil pump gear  anticlockwise until oil flows out of the oil line  without

bubbles.

300653-10

Page 59

MAINTENANCE WORK ON CHASSIS AND ENGINE 57

– Connect the oil line . – Position the oil pump. – Mount and tighten screws .

Guideline

Screw, oil pump M5 6 Nm (4.4 lbf ft)

300651-10

9.85Checking gear oil level

Info

The gear oil level must be checked when the engine is cold.

– Stand the motorcycle upright on a horizontal surface.

Condition

Engine is cold.

– Remove gear oil level check screw . Stand the vehicle upright. – Check the gear oil level.

9.86Changing the gear oil x

700525-01

400721-01

A small amount of gear oil should flow out.

» If no gear oil flows out:

–

Add gear oil. x ( p. 58)

– Mount and tighten the gear oil level check screw.

Guideline

Screw, gear oil level check M6 10 Nm

–

Drain the gear oil. x ( p. 58)

–

Fill up with gear oil. x ( p. 58)

(7.4 lbf ft)

400722-01

Page 60

MAINTENANCE WORK ON CHASSIS AND ENGINE 58

9.87Draining the gear oil x

Warning

Danger of scalding Engine oil and gear oil get very hot when the motorcycle is ridden.

– Wear appropriate protective clothing and safety gloves. In case of burns, rinse immediately with lukewarm water.

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

Drain the gear oil only when the engine is warm.

– Stand the motorcycle on its side stand on a horizontal surface. – Place a suitable container under the engine. – Remove the oil drain plug with magnet . – Completely drain the gear oil. – Thoroughly clean the oil drain plug with magnet. – Clean the sealing area on the engine. – Fit and tighten the oil drain plug with magnet and seal ring.

Guideline

700515-01

Oil drain plug with magnet M12x1.5 20 Nm

(14.8 lbf ft)

9.88Filling up with gear oil x

Info

Too little gear oil or poor-quality oil results in premature wear of the transmission.

– Remove screw cap  and fill up with gear oil.

Gear oil 0.20 l (0.21 qt.) Gear oil (ATF Dexron 3) ( p. 76)

– Mount and tighten screw cap.

Danger

Danger of poisoning Exhaust gases are poisonous and can result in uncon-

sciousness and/or death.

– When running the engine, always make sure there is sufficient venti-

700516-01

lation, and do not start or run the engine in a closed space without an effective exhaust extraction system.

– Start the engine and check that it is oil-tight. – Check the gear oil level. ( p. 57)

9.89Adding gear oil x

Info

Too little gear oil or poor-quality oil results in premature wear of the transmission.

700525-01

– Remove gear oil level check screw .

Page 61

MAINTENANCE WORK ON CHASSIS AND ENGINE 59

– Remove screw cap . Stand the vehicle upright. – Add gear oil until it flows out of the bore of the gear oil level screw.

Gear oil (ATF Dexron 3) ( p. 76)

– Mount and tighten the gear oil level check screw.

Guideline

Screw, gear oil level check M6 10 Nm (7.4 lbf ft)

– Mount and tighten screw cap .

300660-11

Danger

Danger of poisoning Exhaust gases are poisonous and can result in uncon-

sciousness and/or death.

– When running the engine, always make sure there is sufficient venti-

lation, and do not start or run the engine in a closed space without an effective exhaust extraction system.

– Start the engine and check that it is oil-tight.

9.90Checking clutch engagement speed x

– Connect special tool .

Tachometer (45129075000)

Danger

Danger of poisoning Exhaust gases are poisonous and can result in uncon-

sciousness and/or death.

– When running the engine, always make sure there is sufficient venti-

300658-10

– Start the motorcycle. – Slowly increase engine speed until the clutch begins to engage. – Measure the engine speed.

Clutch engagement speed 7,200… 7,500 rpm

» If the specified value is not reached:

–

Adjust the clutch engagement speed. x ( p. 59)

9.91Adjust the clutch engagement speed x

Info

All clutch springs on a vehicle must be marked with the same color.

–

Check the clutch engagement speed. x ( p. 59)

–

Remove the centrifugal clutch. x ( p. 60)

–

Dismantle the centrifugal clutch. x ( p. 62)

Clutch spring with green mark

– Correct the washer  according to the measured value.

Guideline

A washer of 0.2 mm (0.008 in) changes the clutch engagement speed by about:

lation, and do not start or run the engine in a closed space without an effective exhaust extraction system.

100 rpm

300666-01

Info

The spacing washer  of 1.2 mm (0.047 in) )must always be fitted. If you fit the washer , the clutch engagement speed is increased. If you remove the washer , the clutch engagement speed is reduced.

Page 62

MAINTENANCE WORK ON CHASSIS AND ENGINE 60

Clutch spring with yellow mark

– Correct the washer  according to the measured value.

Guideline

301870-01

9.92Removing centrifugal clutch x

A washer of 0.2 mm (0.008 in) changes the clutch engagement speed by about:

Info

The spacing washer  of 1.7 mm (0.067 in) and the spacing washer  of 0.5 mm (0.02 in) must always be fitted. If you fit the washer , the clutch engagement speed is increased. If you remove the washer , the clutch engagement speed is reduced.

–

Assemble the centrifugal clutch. x ( p. 62)

–

Fit the centrifugal force clutch. x ( p. 61)

–

Check the clutch engagement speed. x ( p. 59)

– Remove nut . – Disconnect spring . – Take off the footbrake pedal.

100 rpm

300654-10

300655-10

300656-10

– Lay the motorcycle on its side. – Remove screws . – Take off the clutch cover.

– Hold the clutch drum using the special tool .

Holding spanner (54629012100)

– Remove screw . – Remove the clutch drum.

– Take off the centrifugal clutch .

300657-10

Page 63

MAINTENANCE WORK ON CHASSIS AND ENGINE 61

9.93Fitting centrifugal force clutch x

– Position the centrifugal force clutch .

300657-11

– Position the clutch drum. – Hold the clutch drum with the special tool . – Mount and tighten screw .

Guideline

Screw, clutch drum M8 30 Nm

(22.1 lbf ft)

300656-11

– Position the clutch cover with the gasket. – Mount and tighten screws .

Guideline

Screw, clutch cover M6 10 Nm (7.4 lbf ft)

Loctite®243™

9.94Checking/measuring clutch x

300655-11

300654-11

300610-10

– Position the foot brake pedal. – Mount and tighten nut .

Guideline

Remaining nuts, chassis M8 30 Nm

– Mount the spring . – Check the gear oil level. ( p. 57)

–

Check the clutch engagement speed. x ( p. 59)

Condition

Centrifugal clutch removed. – Measure clutch.

Guideline

Clutch shoe height ≥ 98.00 mm (≥ 3.8583 in)

» if the specified value is not met:

– Replace the clutch linings.

–

Dismantle the centrifugal clutch. x ( p. 62)

– Check clutch linings for damage.

» If the clutch linings are damaged:

– Replace the clutch linings.

–

Assemble the centrifugal clutch. x ( p. 62)

(22.1 lbf ft)

Page 64

MAINTENANCE WORK ON CHASSIS AND ENGINE 62

9.95Dismantling centrifugal clutch x

Condition

Centrifugal clutch removed. – Loosen screws  with special tool.

Mortise key (45229021000)

300513-10

Clutch spring with green mark

– Remove screw  with spacing washer  and spring .

Info

Washer  is used for adjusting the clutch engagement speed and does not have to be fitted. All clutch springs must be marked with the same color.

– Remove clutch shoe .

300514-10

– Repeat these steps on the other clutch shoes.

Clutch spring with yellow mark

– Remove screw  with spacing washers  and spring .

301866-10

9.96Assembling centrifugal clutch x

300514-11

Info

Washer  is used for adjusting the clutch engagement speed and does not have to be fitted. All clutch springs must be marked with the same color.

– Remove clutch shoe . – Repeat these steps on the other clutch shoes.

Condition

Centrifugal clutch removed.

Clutch spring with green mark

– Position the clutch shoe . – Fit screw  with spacing washer  and spring .

Info

Washer  is used for adjusting the clutch engagement speed and must be fitted consistently on all clutch shoes depending on the clutch engagement speed. All clutch springs must be marked with the same color.

– Repeat these steps on the other clutch shoes.

Clutch spring with yellow mark

– Position the clutch shoe . – Fit screw  with spacing washers  and spring .

301866-11

Info

– Repeat these steps on the other clutch shoes.

Page 65

MAINTENANCE WORK ON CHASSIS AND ENGINE 63

– Tighten screws  with special tool.

Guideline

Screw, clutch spring M6 7 Nm (5.2 lbf ft)

Mortise key (45229021000)

300513-11

Page 66

TROUBLESHOOTING 64

Faults Possible cause Action

Engine turns but does not start Operating error – Go through the steps of starting the engine.

( p. 15)

Motorcycle was out of use for a long time and there is old fuel in the float chamber

Fuel feed interrupted – Check the fuel tank breather.

Engine flooded – Clean and dry the spark plug, or change it if

Spark plug oily or wet – Clean and dry the spark plug, or change it if

Electrode distance (plug gap) of spark plug too wide

Fault in ignition system – Short-circuit cable in cable harness

frayed, short-circuit button defective Socket connector or ignition coil is

loose or oxidized Water in carburetor or jets blocked

Engine has no idle Idling jet blocked

Adjusting screws on carburetor distorted

Spark plug defective – Change spark plug. Ignition system defective –

Engine does not speed up Carburetor running over because float

needle dirty or worn

Loose carburetor jets

Fault in ignition system –

Engine has too little power Fuel feed interrupted – Check the fuel tank breather.

Air filter very dirty –

–

Empty the carburetor float chamber. x

– Clean the fuel tap.

(50 SX Mini)

–

Check/set the carburetor components. x

(50 SX)

–

Check/set the carburetor components. x

necessary.

– Adjust the plug gap.

Guideline Spark plug electrode gap

0.60 mm (0.0236 in)

Check the ignition system. x

–

Check the short circuit button. x

– Clean the socket connector and treat it with

contact spray.

(50 SX Mini)

–

Check/set the carburetor components. x

(50 SX)

–

Check/set the carburetor components. x

(50 SX Mini)

–

Check/set the carburetor components. x

(50 SX)

–

Check/set the carburetor components. x

(50 SX Mini)

–

Carburetor - adjust the idle speed. x

( p. 55)

(50 SX)

–

Carburetor - adjust the idle speed. x

( p. 54)

Check the ignition coil. x

–

Check the spark plug connector. x

(50 SX Mini)

–

Check/set the carburetor components. x

(50 SX)

–

Check/set the carburetor components. x

(50 SX Mini)

–

Check/set the carburetor components. x

(50 SX)

–

Check/set the carburetor components. x

Check the ignition system. x

– Clean the fuel tap.

(50 SX Mini)

–

Check/set the carburetor components. x

(50 SX)

–

Check/set the carburetor components. x

Clean the air filter. x ( p. 53)

Page 67

TROUBLESHOOTING 65

Faults Possible cause Action

Engine has too little power Exhaust system leaky, deformed or

too little glass fiber yarn filling in main silencer

Ignition system defective –

Diaphragm or reed valve housing damaged

Noticeable wear – Overhaul the engine. Clutch engagement speed too low or

too high

Engine stalls or is popping into the carburetor

Engine overheats Too little coolant in cooling system – Check the cooling system for leakage.

White smoke emission (steam in exhaust gas)

Gear oil exits at the vent hose Too much gear oil added – Check the gear oil level. ( p. 57) Water in the gear oil Damaged shaft seal ring or water

Lack of fuel – Turn the knurled screw on the fuel tap all the

Engine takes in bad air – Check the intake flange and carburetor for

Socket connector or ignition coil is loose or oxidized

Too little air stream – Switch off engine when standing. Radiator fins very dirty – Clean radiator fins. Foam formation in cooling system –

Damaged cylinder head or cylinder head gasket

Bent radiator hose – Damaged cylinder head or cylinder

head gasket

pump

– Check exhaust system for damage. – Change the glass fiber yarn filling of the main

silencer. x Check the ignition coil. x

–

Check the spark plug connector. x

– Check the diaphragm and reed valve housing.

–

Check the clutch engagement speed. x

( p. 59)

way counterclockwise.

– Fill up with fuel. ( p. 17)

tightness.

– Clean the socket connector and treat it with

contact spray.

– Check the coolant level. ( p. 49)

Drain the coolant. x ( p. 50)

–

Refill the coolant. x ( p. 50)

– Check the cylinder head or cylinder head gas-

ket.

Change the radiator hose. x

– Check the cylinder head or cylinder head gas-

ket.

– Check the shaft seal ring and water pump.

Page 68

CLEANING 66

11.1Cleaning motorcycle

Note

Material damage Damage and destruction of components by high-pressure cleaning equipment.

– Never clean the vehicle with high-pressure cleaning equipment or a strong water-jet. The excessive pressure can penetrate electri-

cal components, socket connects, throttle cables, and bearings, etc., and can damage or destroy these parts.

Warning

Environmental hazard Hazardous substances cause environmental damage.

– Oil, grease, filters, fuel, cleaners, brake fluid, etc., should be disposed of as stipulated in applicable regulations.

Info

If you clean the motorcycle regularly, its value and appearance are maintained over a long period. Avoid direct sunshine on the motorcycle during cleaning.

– Before you clean the motorcycle, seal the exhaust system to prevent penetration by water. – First remove coarse dirt particles with a gentle water spray. – Spray very dirty areas with a normal motorcycle cleaner and then clean with a brush.

Motorcycle cleaner ( p. 78)

Info

Use warm water containing normal motorcycle cleaner and a soft sponge.

– After rinsing the motorcycle with a gentle water spray, allow it to dry thoroughly.

Warning

Danger of accidents Reduced braking efficiency due to wet or dirty brakes.

– Clean or dry dirty or wet brakes by riding and braking gently.

– After cleaning, let your child ride the vehicle a short distance until the engine warms up and the brakes are dried.

Info

The heat produced causes water at inaccessible positions in the engine and the brakes to evaporate.

– Push back the protection covers on the handlebar instruments to allow water to evaporate. – After the motorcycle has cooled off, oil or grease all moving parts and bearings. – Clean the chain. ( p. 33) – Treat bare metal parts (except for brake discs and exhaust system) with anti-corrosion materials.

Cleaning and polishing materials for metal, rubber and plastic ( p. 78)

– Treat all plastic parts and powder-coated parts with a mild cleaning and care product.

Cleaning and polishing materials for metal, rubber and plastic ( p. 78)

– To prevent electrical problems, treat electric contacts and switches with contact spray.

Contact spray ( p. 78)

Page 69

STORAGE 67

12.1Storage

Warning

Danger of poisoning Fuel is poisonous and a health hazard.

– Avoid contact between fuel and skin, eyes and clothing. Do not inhale fuel vapors. If fuel gets into your eyes, rinse immedi-

ately with water and contact a doctor. Wash affected skin areas immediately with soap and water. If fuel is swallowed, contact a doctor immediately. Change clothing that has come into contact with fuel. Store fuel in a suitable canister according to regulations and keep it out of the reach of children.

Info

If you want to garage the motorcycle for a longer period, take the following actions. Before storing the motorcycle, check all parts for function and wear. If service, repairs or replacements are necessary, you should do this during the storage period (less workshop overload). In this way, you can avoid long workshop waiting times at the start of the new season.

– Clean the motorcycle. ( p. 66)

–

Change the gear oil. x ( p. 57)

– Check the antifreeze and coolant level. ( p. 49) – Drain the fuel from the tank into a suitable container. – Check the tire air pressure. ( p. 47) – The storage place should be dry and not subject to large temperature fluctuations.

Info

KTM recommends jacking up the motorcycle.

– Jack up the motorcycle. ( p. 20) – Cover the motorcycle with a porous sheet or blanket. Do not use non-porous materials since they prevent humidity from escaping,

thus causing corrosion.

Info

Avoid running the engine for a short time only. Since the engine cannot warm up properly, the water vapor produced during combustion condenses and causes valves and exhaust system to rust.

12.2Putting into operation after storage

– Remove the motorcycle from the work stand. ( p. 20) – Fill up with fuel. ( p. 17) – Checks before putting into operation. ( p. 15) – Take a test ride.

Page 70

TECHNICAL DATA - ENGINE 68

Design 1-cylinder 2-stroke engine, water-cooled, with reed intake Displacement 49.0 cm³ (2.99 cu in) Stroke 40 mm (1.57 in) Bore 39.5 mm (1.555 in) Crankshaft bearing 2 grooved ball bearings Conrod bearing Needle bearing Piston pin bearing Needle bearing Pistons Aluminum cast Piston rings 1 rectangular ring Engine lubrication (50 SX) Mixture oil lubrication Engine lubrication (50 SX Mini) Separate lubrication Primary transmission 61:33 straight cut spur gear Clutch 3-lining automatic clutch on the main shaft / centrifugal force Gearbox Rigid 1-stage reduction gear Transmission ratio 19:42 Ignition SELETTRA 2p D36 Spark plug NGK LR 8 B Spark plug electrode gap 0.60 mm (0.0236 in) Cooling Water-cooled Starting aid Kickstarter

13.1Capacity - gear oil

Gear oil 0.20 l (0.21 qt.) Gear oil (ATF Dexron 3) ( p. 76)

13.2Capacity - coolant

Coolant 0.5 l (0.5 qt.) Coolant ( p. 76)

Coolant (mixed ready to use) ( p. 76)

Page 71

TECHNICAL DATA - ENGINE TIGHTENING TORQUES 69

Screw, bearing retainer M5 5 Nm (3.7 lbf ft) – Screw, kickstarter M5 6 Nm (4.4 lbf ft) Screw, oil pump (50 SX Mini) M5 6 Nm (4.4 lbf ft) – Screw, stator clamp M5 6 Nm (4.4 lbf ft) – Screw, water pump wheel M5 5 Nm (3.7 lbf ft) Bleeder flange of engine case M6 4 Nm (3 lbf ft) Screw generator cover M6 6 Nm (4.4 lbf ft) – Screw, clutch cover M6 10 Nm (7.4 lbf ft) – Screw, clutch spring M6 7 Nm (5.2 lbf ft) – Screw, engine housing M6 10 Nm (7.4 lbf ft) – Screw, engine sprocket cover M6 10 Nm (7.4 lbf ft) – Screw, exhaust flange M6 10 Nm (7.4 lbf ft) – Screw, gear oil level check M6 10 Nm (7.4 lbf ft) – Screw, ignition coil M6 5 Nm (3.7 lbf ft) – Screw, intake flange M6 5 Nm (3.7 lbf ft) Screw, water pump cover M6 10 Nm (7.4 lbf ft) – Screw, cyliner head M7 18 Nm (13.3 lbf ft) – Nuts, cylinder base M8 20 Nm (14.8 lbf ft) – Screw, clutch drum M8 30 Nm (22.1 lbf ft) Stud bolt, cylinder base M8 10 Nm (7.4 lbf ft) – Spark plug M10x1 10… 12 Nm (7.4…

8.9 lbf ft) Nut, primary gear M10x1.25 40 Nm (29.5 lbf ft) Nut, rotor M10x1.25 15 Nm (11.1 lbf ft) – Oil drain plug with magnet M12x1.5 20 Nm (14.8 lbf ft) –

Loctite®243™

–

Loctite®243™

Page 72

TECHNICAL DATA - CARBURETOR 70

15.150 SX

Carburetor type Dell`Orto PHBG 19BS Needle position 3rd position from top Idle mixture adjusting screw

Open 3 turns Main jet 85 Jet needle W9 Idling jet 58 Needle jet 260AU Throttle slide 60 Cold start jet 60

15.250 SX Mini

Carburetor type Dell`Orto PHVA 12XS Needle position 4th position from top Idle air adjusting screw

Open 1 turn Main jet 60 Jet needle A10 Idling jet 35 Needle jet 211FA Throttle slide 40 Cold start jet 60

Page 73

TECHNICAL DATA - CHASSIS 71

Frame Central tube frame of chrome molybdenum steel tubing, powder-

coated Fork Marzocchi Shock absorber WP Suspension 3614 BAEM Suspension travel (50 SX)

Front 185 mm (7.28 in) Rear 185 mm (7.28 in)

Suspension travel (50 SX Mini)

Front 110 mm (4.33 in)

Rear 171 mm (6.73 in) Fork offset 14 mm (0.55 in) Brake system

Front Disc brake, brake caliper, fixed

Rear Disc brake, brake caliper, fixed Brake disc diameters

Front 160 mm (6.3 in)

Rear 140 mm (5.51 in) Brake discs - wear limits

Front 2.2 mm (0.087 in)

Rear 2.2 mm (0.087 in) Tire air pressure off road

Front 1.0 bar (15 psi)

Rear 1.0 bar (15 psi) Secondary drive ratio (50 SX) 11:40 Secondary drive ratio (50 SX Mini) 10:42 Chain 1/2 x 3/16” Rear sprockets available 38, 39, 40, 41, 42 Steering head angle (50 SX) 66° Steering head angle (50 SX Mini) 67.4° Wheelbase (50 SX) 1,032 mm (40.63 in) Wheelbase (50 SX Mini) 914 mm (35.98 in) Seat height unloaded (50 SX) 684 mm (26.93 in) Seat height unloaded (50 SX Mini) 558 mm (21.97 in) Ground clearance unloaded (50 SX) 252 mm (9.92 in) Ground clearance unloaded (50 SX Mini) 184 mm (7.24 in) Weight without fuel, approx. (50 SX) 39.8 kg (87.7 lb.) Weight without fuel, approx. (50 SX Mini) 39.0 kg (86 lb.)

16.1Tires

Validity Front tire Rear tire

(50 SX) 60/100 - 12 36M TT

Pirelli SCORPION MX Mid Soft 32 NHS

(50 SX Mini) 2.50 - 10 33J TT

Pirelli SCORPION MX Mid Soft 32 NHS

Additional information is available in the Service section under: http://www.ktm.com

2.75 - 10 37J TT

Pirelli SCORPION MX Mid Soft 32 NHS

2.75 - 10 37J TT

Pirelli SCORPION MX Mid Soft 32 NHS

Page 74

TECHNICAL DATA - CHASSIS 72

16.2Capacity - fuel

Fuel tank capacity, approx. (50 SX)

Fuel tank capacity, approx. (50 SX Mini)

2.3 l (2.4 qt.) Super unleaded gasoline, mixed with 2-stroke engine oil (1:60) ( p. 77)

2.0 l (2.1 qt.) Super unleaded (ROZ 95 / RON 95 / PON 91) ( p. 77)

Page 75

TECHNICAL DATA - FORK 73

17.150 SX

Fork part number 45101000644 Fork Marzocchi Spring rate

Weight of rider: 25… 35 kg (55… 77 lb.) 2 N/mm (11 lb/in) Air chamber length 100±2.5 mm (3.94±0.098 in) Fork length 692 mm (27.24 in)

Fork oil 210 ml (7.1 fl. oz.) Fork oil (SAE 7.5) ( p. 76)

17.250 SX Mini

Fork part number 45201000233 Fork Marzocchi Spring rate

Weight of rider: 25… 35 kg (55… 77 lb.) 2 N/mm (11 lb/in) Air chamber length 100±2.5 mm (3.94±0.098 in) Fork length 578 mm (22.76 in)

Fork oil 210 ml (7.1 fl. oz.) Fork oil (SAE 7.5) ( p. 76)

Page 76

TECHNICAL DATA - SHOCK ABSORBER 74

18.150 SX

Shock absorber part number 03.18.9E.02 Shock absorber WP Suspension 3614 BAEM Rebound damping

Standard 10 clicks Spring preload

Standard 3 mm (0.12 in) Spring rate

Weight of rider: < 25 kg (< 55 lb.) 30 N/mm (171 lb/in)

Weight of rider: 25… 35 kg (55… 77 lb.) 35 N/mm (200 lb/in)

Weight of rider: > 40 kg (> 88 lb.) 40 N/mm (228 lb/in) Spring length 130 mm (5.12 in) Gas pressure 10 bar (145 psi) Static sag 20 mm (0.79 in) Riding sag 45… 55 mm (1.77… 2.17 in) Fitted length 275 mm (10.83 in)

Shock absorber oil Shock absorber oil (SAE 2.5) (50180342S1) ( p. 77)

18.250 SX Mini

Shock absorber part number 03.18.9E.04 Shock absorber WP Suspension 3614 BAEM Rebound damping

Standard 12 clicks Spring preload

Standard 5 mm (0.2 in) Spring rate

Weight of rider: < 25 kg (< 55 lb.) 65 N/mm (371 lb/in)

Weight of rider: 25… 35 kg (55… 77 lb.) 75 N/mm (428 lb/in)

Weight of rider: > 35 kg (> 77 lb.) 85 N/mm (485 lb/in) Spring length 120 mm (4.72 in) Gas pressure 10 bar (145 psi) Static sag 15 mm (0.59 in) Riding sag 40… 50 mm (1.57… 1.97 in) Fitted length 245 mm (9.65 in)

Shock absorber oil Shock absorber oil (SAE 2.5) (50180342S1) ( p. 77)

Page 77

TECHNICAL DATA - CHASSIS TIGHTENING TORQUES 75

Spoke nipple M3.5 3 Nm (2.2 lbf ft) – Rear brake caliper screw M6 10 Nm (7.4 lbf ft) Remaining nuts, chassis M6 15 Nm (11.1 lbf ft) – Screw, ball joint, push rod on foot-

brake cylinder Screw, bottom triple clamp M6 10 Nm (7.4 lbf ft) – Screw, front brake disc M6 15 Nm (11.1 lbf ft) Screw, rear brake disc M6 15 Nm (11.1 lbf ft) Screw, rear sprocket M7 15 Nm (11.1 lbf ft) Engine carrying screw M8 25 Nm (18.4 lbf ft) – Nut, rim lock M8 10 Nm (7.4 lbf ft) – Remaining nuts, chassis M8 30 Nm (22.1 lbf ft) – Remaining screws, chassis M8 25 Nm (18.4 lbf ft) – Screw, front brake caliper M8 20 Nm (14.8 lbf ft) Screw, handlebar clamp M8 20 Nm (14.8 lbf ft) – Screw, top triple clamp M8 25 Nm (18.4 lbf ft) – Nut, swingarm pivot M10 45 Nm (33.2 lbf ft) – Remaining nuts, chassis M10 50 Nm (36.9 lbf ft) – Remaining screws, chassis M10 45 Nm (33.2 lbf ft) – Screw, bottom shock absorber M10 45 Nm (33.2 lbf ft) – Screw, handlebar support M10 40 Nm (29.5 lbf ft) Screw, top shock absorber M10 45 Nm (33.2 lbf ft) – Front wheel spindle nut M12x1 40 Nm (29.5 lbf ft) – Nut, rear wheel spindle M12x1 40 Nm (29.5 lbf ft) – Nut, steering stem M20x1.5 10 Nm (7.4 lbf ft) – Steering head nut M20x1.5 10 Nm (7.4 lbf ft) –

M6 10 Nm (7.4 lbf ft) –

Loctite®243™

Page 78

OPERATING SUBSTANCES 76

2-stroke engine oil

According to

– JASO FC ( p. 80)

Guideline

–

Only use high quality 2-stroke engine oil of a well-known brand. KTM recommends Motorex®products.

Fully synthetic

Supplier

Motorex – Cross Power 2T

Brake fluid DOT 4 / DOT 5.1

According to

– DOT

Guideline

– Use only brake fluid that complies with the specified standards (see specifications on the container) and that possesses the corre-

sponding properties. KTM recommends Castrol and Motorex®products.

Supplier Castrol – RESPONSE BRAKE FLUID SUPER DOT 4

Motorex – Brake Fluid DOT 5.1

Coolant

Guideline

– Use only suitable coolant (also in countries with high temperatures). Use of low-quality antifreeze can lead to corrosion and foam-

ing. KTM recommends Motorex®products.

Mixture ratio

Antifreeze protection: −25… −45 °C (−13…

−49 °F)

50 % corrosion inhibitor/antifreeze 50 % distilled water

Coolant (mixed ready to use)

Antifreeze −40 °C (−40 °F)

Supplier

Motorex – Anti Freeze

Fork oil (SAE 7.5)

According to

– SAE ( p. 80) (SAE 7.5)

Guideline

– Use only oils that comply with the specified standards (see specifications on the container) and that possess the corresponding

properties. KTM recommends Motorex®products.

Supplier

Motorex – Racing Fork Oil

Gear oil (ATF Dexron 3)

According to

– Dexron III (ATF Dexron 3)

Guideline

– Use only ATF gear oils that comply with the specified standards (see specifications on the container) and that possess the corre-

sponding properties. KTM recommends Motorex®products.

Supplier

Motorex – ATF Dexron 3

Page 79

OPERATING SUBSTANCES 77

Shock absorber oil (SAE 2.5) (50180342S1)

According to

– SAE ( p. 80) (SAE 2.5)

Guideline

– Use only oils that comply with the specified standards (see specifications on the container) and that possess the corresponding

properties.

Super unleaded (ROZ 95 / RON 95 / PON 91)

According to

– DIN EN 228 (ROZ 95 / RON 95 / PON 91)

Super unleaded gasoline, mixed with 2-stroke engine oil (1:60)

According to

– DIN EN 228 – JASO FC ( p. 80) (1:60)

Mixture ratio

1:60 2-stroke engine oil ( p. 76)

Super unleaded (ROZ 95 / RON 95 / PON 91) ( p. 77)

Page 80

AUXILIARY SUBSTANCES 78

Air filter cleaner

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Twin Air Dirt Bio Remover

Chain cleaner

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Chain Clean 611

Cleaning and polishing materials for metal, rubber and plastic

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Protect & Shine 645

Contact spray

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Accu Contact

Long-life grease

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Fett 2000

Motorcycle cleaner

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Moto Clean 900

Offroad chain spray

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Chain Lube 622

Oil for foam air filter

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Twin Air Liquid Bio Power

Page 81

AUXILIARY SUBSTANCES 79

Universal oil spray

Guideline

–

KTM recommends Motorex®products.

Supplier

Motorex – Joker 440 Universal

Page 82

STANDARDS 80

JASO FC

JASO FC is a classification for a 2-stroke engine oil that was specifically developed for the extreme demands of racing. Thanks to first rate synthetic esters and specially designed additives, superb combustion is achieved even under extreme operating conditions.

SAE

The SAE viscosity classes were defined by the Society of Automotive Engineers and are used for classifying oils according to their viscosity. The viscosity describes only one property of oil and says nothing about quality.

Page 83

INDEX 81

INDEX

Air filter

cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Antifreeze

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Brake discs

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Brake fluid

front brake fluid, adding . . . . . . . . . . . . . . . . . . . . . . 38

of rear brake, adding . . . . . . . . . . . . . . . . . . . . . . . . . 42

Brake fluid level

front brake, checking . . . . . . . . . . . . . . . . . . . . . . . . 37

rear brake, checking . . . . . . . . . . . . . . . . . . . . . . . . . 42

Brake linings

front brake linings, changing . . . . . . . . . . . . . . . . . . . 40

front brake, checking . . . . . . . . . . . . . . . . . . . . . . . . 39

front brake, installing . . . . . . . . . . . . . . . . . . . . . . . . 39

front brake, removing . . . . . . . . . . . . . . . . . . . . . . . . 39

rear brake, changing . . . . . . . . . . . . . . . . . . . . . . . . . 44

rear brake, checking . . . . . . . . . . . . . . . . . . . . . . . . . 43

rear brake, installing . . . . . . . . . . . . . . . . . . . . . . . . . 44

rear brake, removing . . . . . . . . . . . . . . . . . . . . . . . . . 43

Carburetor

idle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53-54

idle speed, adjusting . . . . . . . . . . . . . . . . . . . . . . . 54-55

Centrifugal clutch

adjusting clutch engagement speed . . . . . . . . . . . . . . . 59

removing centrifugal clutch . . . . . . . . . . . . . . . . . . . . 60

Centrifugal force clutch

checking clutch engagement speed . . . . . . . . . . . . . . . 59

fitting centrifugal force clutch . . . . . . . . . . . . . . . . . . 61

Chain

cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Chain guide

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Chain tension

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Chassis number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Choke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Coolant

draining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

refilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Coolant level

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Dust boots

cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Engine

running in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Engine - Work on individual parts

assembling centrifugal clutch . . . . . . . . . . . . . . . . . . . 62

checking/measuring clutch . . . . . . . . . . . . . . . . . . . . . 61

dismantling centrifugal clutch . . . . . . . . . . . . . . . . . . 62

Engine number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Filler cap

closing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Filling up

fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Foot brake pedal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

basic position, adjusting . . . . . . . . . . . . . . . . . . . . . . 41

free travel, checking . . . . . . . . . . . . . . . . . . . . . . . . . 41

Fork legs

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Fork overhang

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Front fender

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Front wheel

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Fuel tap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Fuel, oils, etc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Gear oil

adding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

changing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

draining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

refilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Gear oil level

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Hand brake lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

adjusting play . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

basic position, adjusting . . . . . . . . . . . . . . . . . . . . . . 37

checking play . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Handlebar position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Kickstarter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Lower triple clamp

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Page 84

INDEX 82

Main silencer

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

installing glass fiber yarn filling . . . . . . . . . . . . . . . . . 52

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

removing flass fiber yarn filling . . . . . . . . . . . . . . . . . . 52

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Motorcycle

cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Oil level

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Oil pump

bleeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Oil tank cap

closing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Owner's manual

general information . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Play in throttle cable

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Plug-in stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Putting into operation

advice on first use . . . . . . . . . . . . . . . . . . . . . . . . . . 13

after storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

checks before putting into operation . . . . . . . . . . . . . . 15

Rear sprocket / engine sprocket

checking for wear . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Rear wheel

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Rebound damping

shock absorber, adjusting . . . . . . . . . . . . . . . . . . . . . 20

Riding sag

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Seat

mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Seat height

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Service schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18-19

Shock absorber

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

riding sag, checking . . . . . . . . . . . . . . . . . . . . . . . . . 21

static sag, checking . . . . . . . . . . . . . . . . . . . . . . . . . 21

Shock absorber part number . . . . . . . . . . . . . . . . . . . . . . . . 9

Short circuit button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Spare parts, accessories . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Spoke tension

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Spring preload

shock absorber, adjusting . . . . . . . . . . . . . . . . . . . . . 21

Start number plate

installing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

removing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Steering head bearing

greasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Steering head bearing play

adjusting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Technical data

carburetor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71-72

chassis tightening torques . . . . . . . . . . . . . . . . . . . . . 75

engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

engine tightening torques . . . . . . . . . . . . . . . . . . . . . 69

fork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

shock absorber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Throttle grip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Tire air pressure

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Tire condition

checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64-65

Use definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Vehicle level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

View of vehicle

left front . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

right rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Work rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Page 85

*3211477en*

3211477en

KTM-Sportmotorcycle AG

5230 Mattighofen/Austria

http://www.ktm.com

04/2009

Photo: Mitterbauer

KTM 50 SX MINI, 50 SX User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

MEANS OF REPRESENTATION 4

IMPORTANT INFORMATION 5

VIEW OF VEHICLE 7

3.1View of the vehicle from the left front (example)

3.2View of the vehicle from the right rear (example)

LOCATION OF SERIAL NUMBERS 9

4.1Chassis number

4.2Engine number

4.3Shock absorber part number

CONTROLS 10

5.1Throttle grip

5.2Hand brake lever

5.3Short circuit button

5.4Fuel tap

5.5Opening filler cap

5.6Closing filler cap

5.7Opening oil tank cap (50 SX Mini)

5.8Closing oil tank cap (50 SX Mini)

5.9Choke (50 SX)

5.10Choke (50 SX Mini)

5.11Kickstarter

5.12Foot brake pedal

5.13Plug-in stand

GENERAL TIPS AND HINTS ON PUTTING INTO OPERATION 13

6.1Advice on first use

6.2Running in the engine

RIDING INSTRUCTIONS 15

7.1Checks before putting into operation

7.2Starting

7.3Starting up

7.4Shifting, riding

7.5Braking

7.6Stopping, parking

7.7Refueling

7.8Filling up with oil (50 SX Mini)

SERVICE SCHEDULE 18

8.1Important maintenance work that must be done in an authorized KTM workshop

8.2Important maintenance work that must be done in an authorized KTM workshop (as additional order)

8.3Performance of urgent inspection and care work by the supervisory individual.

MAINTENANCE WORK ON CHASSIS AND ENGINE 20

9.1Jacking up the motorcycle

9.2Removing the motorcycle from the work stand

9.3Adjusting the rebound damping of the shock absorber

9.4Measuring rear wheel sag unloaded

9.5Checking the static sag of the shock absorber

9.6Checking the riding sag of the shock absorber

9.11Vehicle level

9.14Cleaning dust boots of fork legs

9.15Checking play of steering head bearing

9.22Dismounting the front fender

9.23Installing the front fender

9.24Dismounting the start number plate

9.25Installing the start number plate

9.26Handlebar position

9.28Checking the play in the throttle cable

9.30Checking chain dirt

9.31Cleaning the chain

9.32Checking the chain tension

9.33Checking the chain tension - installing rear wheel

9.34Checking rear sprocket / engine sprocket for wear

9.35Adjusting chain tension

9.36Adjusting chain tension - after checking

9.37Adjusting chain tension - installing rear wheel

9.39Checking brake discs

9.40Checking play of handbrake lever

9.41Adjusting play of handbrake lever

9.42Adjusting basic position of handbrake lever

9.43Checking the front brake fluid level

9.45Checking the front brake linings

9.49Checking the free travel of the foot brake lever

9.51Checking rear brake fluid level

9.53Checking the rear brake linings

9.61Checking the tire condition

9.62Checking tire air pressure

9.63Checking spoke tension

9.64Removing the seat