Congratulations on your purchase of a
Yamaha WR series. This model is the culmination of Yamaha’s vast experience in the production of pacesetting racing machines. It
represents the highest grade of craftsmanship
and reliability that have made Yamaha a
leader.
This manual explains operation, inspection,
basic maintenance and tuning of your
machine. If you have any questions about this
manual or your machine, please contact your
Yamaha dealer.
OTE:
As improvements are made on this model,
some data in this manual may become outdated. If you have any questions, please consult your Yamaha dealer.
WARNING
PLEASE READ THIS MANUAL CAREFULLY
AND COMPLETELY BEFORE OPERATING
THIS MACHINE. DO NOT ATTEMPT TO
OPERATE THIS MACHINE UNTIL YOU
HAVE ATTAINED A SATISFACTORY
KNOWLEDGE OF ITS CONTROLS AND
OPERATING FEATURES AND UNTIL YOU
HAVE BEEN TRAINED IN SAFE AND
PROPER RIDING TECHNIQUES. REGULAR
INSPECTIONS AND CAREFUL MAINTENANCE, ALONG WITH GOOD RIDING
SKILLS, WILL ENSURE THAT YOU SAFETY
ENJOY THE CAPABILITIES AND THE RELIABILITY OF THIS MACHINE.
Page 5
Page 6
IMPORTANT NOTICE
THIS MACHINE IS DESIGNED STRICTLY
FOR COMPETITION USE, ONLY ON A
CLOSED COURSE. It is illegal for this
machine to be operated on any public street,
road, or highway. Off-road use on public lands
may also be illegal. Please check local regulations before riding.
SAFETY INFORMATION
1. THIS MACHINE IS TO BE OPERATED
BY AN EXPERIENCED RIDER ONLY.
Do not attempt to operate this
machine at maximum power until you
are totally familiar with its characteristics.
2. THIS MACHINE IS DESIGNED TO BE
RIDDEN BY THE OPERATOR ONLY.
Do not carry passengers on this
machine.
3. ALWAYS WEAR PROTECTIVE
APPAREL.
When operating this machine, always
wear an approved helmet with goggles or a face shield. Also wear heavy
boots, gloves, and protective clothing. Always wear proper fitting clothing that will not be caught in any of
the moving parts or controls of the
machine.
4. ALWAYS MAINTAIN YOUR MACHINE
IN PROPER WORKING ORDER.
For safety and reliability, the machine
must be proerly maintained. Always
perform the pre-operation checks
indicated in this manual. Correcting a
mechanical problem before you ride
may prevent an accident.
5. GASOLINE IS HIGHLY FLAMMABLE.
Always turn off the engine while refueling. Take care to not spill any gasoline on the engine or exhaust system.
Never refuel in the vicinity of an open
flame, or while smoking.
Page 7
6. GASOLINE CAN CAUSE INJURY.
If you should swallow some gasoline,
inhale excess gasoline vapors, or
allow any gasoline to get into your
eyes, contact a doctor immediately. If
any gasoline spills onto your skin or
clothing, immediately wash skin
areas with soap and water, and
change your clothes.
7. ONLY OPERATE THE MACHINE IN AN
AREA WITH ADEQUATE VENTILATION.
Never start the engine or let it run for
any length of time in an enclosed
area.
Exhaust fumes are poisonous. These
fumes contain carbon monoxide,
which by itself is odorless and colorless. Carbon monoxide is a dangerous gas which can cause
unconsciousness or can be lethal.
8. PARK THE MACHINE CAREFULLY;
TURN OFF THE ENGINE.
Always turn off the engine if you are
going to leave the machine. Do not
park the machine on a slope or soft
ground as it may fall over.
9. THE ENGINE, EXHAUST PIPE, MUFFLER, AND OIL TANK WILL BE VERY
HOT AFTER THE ENGINE HAS BEEN
RUN.
Be careful not to touch them or to
allow any clothing item to contact
them during inspection or repair.
10. PROPERLY SECURE THE MACHINE
BEFORE TRANSPORTING IT.
When transporting the machine in
another vehicle, always be sure it is
properly secured and in an upright
position and that the fuel cock is in
the “OFF” position. Otherwise, fuel
may leak out of the carburetor or fuel
tank.
Page 8
EC050000
TO THE NEW OWNER
This manual will provide you with a good basic
understanding of features, operation, and
basic maintenance and inspection items of this
machine. Please read this manual carefully
and completely before operating your new
machine. If you have any questions regarding
the operation or maintenance of your machine,
please consult your Yamaha dealer.
OTE:
This manual should be considered a permanent part of this machine and should remain
with it even if the machine is subsequently
sold.
EC060000
NOTICE
Some data in this manual may become outdated due to improvements made to this
model in the future. If there is any question
you have regarding this manual or your
machine, please consult your Yamaha
dealer.
EC070001
F.I.M. MACHINE WEIGHTS:
Weights of machines without fuel
The minimum weights for motocross
machines are:
for the class 125 cc....................... minimum
88 kg (194 lb)
for the class 250 cc....................... minimum
98 kg (216 lb)
for the class 500 cc....................... minimum
102 kg (225 lb)
In modifying your machine (e.g., for weight
reduction), take note of the above limits of
weight.
Page 9
EC080000
WARNING
HOW TO USE
THIS MANUAL
EC081000
PARTICULARLY IMPORTANT
INFORMATION
The Safety Alert Symbol means ATTENTION!
BECOME ALERT! YOUR SAFETY IS
INVOLVED!
Failure to follow WARNING instructions could
result in severe injury or death to the machine
operator, a bystander, or a person inspecting
or repairing the machine.
CAUTION:
A CAUTION indicates special precautions that
must be taken to avoid damage to the
machine.
NOTE:
A NOTE provides key information to make procedures easier or clearer.
EC082000
FINDING THE REQUIRED PAGE
1. This manual consists of seven chapters;
“General information”, “Specifications”,
“Regular inspection and adjustments”,
“Engine”, “Chassis”, “Electrical” and “Tun-
ing”.
2. The table of contents is at the beginning of
the manual. Look over the general layout of
the book before finding then required chapter and item.
Bend the book at its edge, as shown, to
find the required fore edge symbol mark
and go to a page for required item and
description.
Page 10
EC083000
MANUAL FORMAT
All of the procedures in this manual are organized in a sequential, step-by-step format. The information has been complied to provide the mechanic with an easy to read, handy reference that contains
comprehensive explanations of all disassembly, repair, assembly, and inspection operations.
In this revised format, the condition of a faulty component will precede an arrow symbol and the
course of action required will follow the symbol, e.g.,
• Bearings
Pitting/damage → Replace.
EC084002
HOW TO READ DESCRIPTIONS
To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each
removal and disassembly section.
1. An easy-to-see exploded diagram 1 is provided for removal and disassembly jobs.
2. Numbers 2 are given in the order of the jobs in the exploded diagram. A number that is
enclosed by a circle indicates a disassembly step.
3. An explanation of jobs and notes is presented in an easy-to-read way by the use of symbol
marks 3. The meanings of the symbol marks are given on the next page.
4. A job instruction chart 4 accompanies the exploded diagram, providing the order of jobs, names
of parts, notes in jobs, etc.
5. Extent of removal 5 is provided in the job instruction chart to save the trouble of an unneces-
sary removal job.
6. For jobs requiring more information, the step-by-step format supplements 6 are given in addi-
tion to the exploded diagram and job instruction chart.
Page 11
12
GEN
INFO
34
SPEC
INSP
ADJ
56
CHAS
ENG
–+
ELEC
ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols 1 to 7 are designed as
thumb tabs to indicate the chapter’s number
and content.
General information
1
Specifications
2
Regular inspection and adjustments
3
Engine
4
Chassis
5
Electrical
6
Tuning
7
78
TUN
90
AB
T
.
R
.
CD
EF
Illustrated symbols 8 to D are used to identify
the specifications appearing in the text.
With engine mounted
8
Special tool
9
Filling fluid
0
Lubricant
A
Tightening
B
Specified value, Service limit
C
Resistance (Ω), Voltage (V), Electric current (A)
D
Illustrated symbols E to H in the exploded
diagrams indicate grade of lubricant and location of lubrication point.
E
GH
B
IJ
M
M
New
Apply engine oil
E
Apply molybdenum disulfide oil
F
Apply lightweight lithium-soap base grease
G
Apply molybdenum disulfide grease
H
Illustrated symbols I to J in the exploded
diagrams indicate where to apply a locking
agent and where to install new parts.
®
Apply locking agent (LOCTITE
I
Use new one
J
)
Page 12
MEMO
Page 13
EC090000
INDEX
GENERAL INFORMATION
SPECIFICATIONS
REGULAR INSPECTION AND ADJUSTMENTS
ENGINE
CHASSIS
GEN
INFO
SPEC
INSP
ADJ
ENG
CHAS
1
2
3
4
5
ELECTRICAL
TUNING
–+
ELEC
6
TUN
7
Page 14
EC0A0000
CONTENTS
CHAPTER 1
GENERAL INFORMATION
DESCRIPTION
MACHINE IDENTIFICATION
IMPORTANT INFORMATION
CHECKING OF CONNECTION
SPECIAL TOOLS
CONTROL FUNCTIONS
FUEL
STARTING AND BREAK-IN
TORQUE-CHECK POINTS
CLEANING AND STORAGE
SEAT, FUEL TANK AND
SIDE COVERS
EXHAUST PIPE AND SILENCER
RADIATOR
CARBURETOR
CAMSHAFTS
CYLINDER HEAD
VALVES AND VALVE SPRINGS
CYLINDER AND PISTON
CLUTCH
OIL FILTER ELEMENT, WATER PUMP
AND RIGHT CRANKCASE COVER
BALANCER
OIL PUMP
KICK SHAFT AND SHIFT SHAFT
AC MAGNETO AND
STARTER CLUTCH
ENGINE REMOVAL
CRANKCASE AND CRANKSHAFT
TRANSMISSION, SHIFT CAM AND
SHIFT FORK
ELECTRICAL COMPONENTS AND
WIRING DIAGRAM
MAP-CONTROLLED CDI UNIT
IGNITION SYSTEM
ELECTRIC STARTING SYSTEM
CHARGING SYSTEM
THROTTLE POSITION SENSOR
SYSTEM
LIGHTING SYSTEM
1 Clutch lever
2 Hot starter lever
3 Engine stop switch
4 Trip meter
5 Main switch
6 Light switch
7 Start switch
8 Front brake lever
9 Throttle grip
0 Radiator cap
A Fuel tank cap
B Taillight
C Kickstarter crank
D Fuel tank
E Headlight
F Radiator
G Coolant drain bolt
H Rear brake pedal
I Valve joint
J Fuel cock
K Cold starter knob
L Air cleaner
M Drive chain
N Shift pedal
O Oil dipstick
P Front fork
GEN
DESCRIPTION
OTE:
• The machine you have purchased may differ
slightly from those shown in the following.
• Designs and specifications are subject to
change without notice.
3
2
1
A
INFO
4
5
6
0
7
8
9
1
B
CD
GH
E
F
P
O
IJ
K
L
MN
1 - 1
Page 18
1
MACHINE IDENTIFICATION
EC120001
MACHINE IDENTIFICATION
There are two significant reasons for knowing
the serial number of your machine:
1. When ordering parts, you can give the
number to your Yamaha dealer for positive
identification of the model you own.
2. If your machine is stolen, the authorities will
need the number to search for and identify
your machine.
EC121001
VEHICLE IDENTIFICATION NUMBER
The vehicle identification number 1 is
stamped on the right of the steering head pipe.
GEN
INFO
1
1
EC123001
ENGINE SERIAL NUMBER
The engine serial number 1 is stamped into
the elevated part of the right-side of the
engine.
EC124000
MODEL LABEL
The model label 1 is affixed to the frame
under the rider’s seat. This information will be
needed to order spare parts.
1 - 2
Page 19
IMPORTANT INFORMATION
EC130000
IMPORTANT INFORMATION
EC131010
PREPARATION FOR REMOVAL AND
DISASSEMBLY
1. Remove all dirt, mud, dust, and foreign
material before removal and disassembly.
When washing the machine with high pressured water, cover the parts follows.
• Silencer exhaust port
• Side cover air intake port
• Water pump housing hole at the bottom
• Drain hole on the cylinder head
(right side)
• All electrical components
GEN
INFO
2. Use proper tools and cleaning equipment.
Refer to “SPECIAL TOOLS” section.
3. When disassembling the machine, keep
mated parts together. They include gears,
cylinders, pistons, and other mated parts
that have been “mated” through normal
wear. Mated parts must be reused as an
assembly or replaced.
4. During the machine disassembly, clean all
parts and place them in trays in the order of
disassembly. This will speed up assembly
time and help assure that all parts are correctly reinstalled.
5. Keep away from fire.
1 - 3
Page 20
IMPORTANT INFORMATION
EC132000
ALL REPLACEMENT PARTS
1. We recommend to use Yamaha genuine
parts for all replacements. Use oil and/or
grease recommended by Yamaha for
assembly and adjustment.
EC133000
GASKETS, OIL SEALS AND O-RINGS
1. All gaskets, oil seals, and O-rings should
be replaced when an engine is overhauled.
All gasket surfaces, oil seal lips, and Orings must be cleaned.
2. Properly oil all mating parts and bearings
during reassembly. Apply grease to the oil
seal lips.
GEN
INFO
EC134000
LOCK WASHERS/PLATES AND COTTER
PINS
1. All lock washers/plates 1 and cotter pins
must be replaced when they are removed.
Lock tab(s) should be bent along the bolt or
nut flat(s) after the bolt or nut has been
properly tightened.
EC135001
BEARINGS AND OIL SEALS
1. Install the bearing(s) 1 and oil seal(s) 2
with their manufacturer’s marks or numbers
facing outward. (In other words, the
stamped letters must be on the side
exposed to view.) When installing oil
seal(s), apply a light coating of lightweight
lithium base grease to the seal lip(s). Oil
the bearings liberally when installing.
CAUTION:
Do not use compressed air to spin the
bearings dry. This causes damage to the
bearing surfaces.
1 - 4
Page 21
IMPORTANT INFORMATION
EC136000
CIRCLIPS
1. All circlips should be inspected carefully
before reassembly. Always replace piston
pin clips after one use. Replace distorted
circlips. When installing a circlip 1, make
sure that the sharp-edged corner 2 is positioned opposite to the thrust 3 it receives.
See the sectional view.
Shaft
4
GEN
INFO
1 - 5
Page 22
CHECKING OF CONNECTION
EC1C0001
CHECKING OF CONNECTION
Dealing with stains, rust, moisture, etc. on the
connector.
1. Disconnect:
• Connector
2. Dry each terminal with an air blower.
3. Connect and disconnect the connector two
or three times.
4. Pull the lead to check that it will not come
off.
5. If the terminal comes off, bend up the pin
1 and reinsert the terminal into the connector.
GEN
INFO
6. Connect:
• Connector
OTE:
The two connectors “click” together.
7. Check for continuity with a tester.
OTE:
• If there in no continuity, clean the terminals.
• Be sure to perform the steps 1 to 7 listed
above when checking the wire harness.
• For a field remedy, use a contact revitalizer
available on the market.
• Use the tester on the connector as shown.
1 - 6
Page 23
GEN
SPECIAL TOOLS
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the
correct special tool will help prevent damage caused by the use of improper tools or improvised
techniques. The shape and part number used for the special tool differ by country, so two types are
provided. Refer to the list provided to avoid errors when placing an order.
OTE:
• For U.S.A. and Canada, use part number starting with “YM-”, “YU-” or “ACC-”.
• For others, use part number starting with “90890-”.
Part numberTool name/How to useIllustration
YU-1135-A, 90890-01135Crankcase separating tool
These tool is used to remove the crankshaft from
either case.
YU-3097, 90890-01252
YU-1256
Dial gauge and stand
Stand
INFO
These tools are used to check each part for runout or
bent.
These tools are used for checking the cooling sys-
tem.
This tool is used when tighten the steering ring nut to
specification.
Use this tool to remove and install the damper rod.
1 - 7
Page 24
SPECIAL TOOLS
Part numberTool name/How to useIllustration
YM-01442, 90890-01442Fork seal driver
This tool is used when install the fork oil seal.
YU-3112-C, 90890-03112Pocket tester
Use this tool to inspect the coil resistance, output
voltage and amperage.
YU-8036-B
90890-03113
YM-33277-A, 90890-03141 Timing light
Inductive tachometer
Engine tachometer
This tool is needed for observing engine rpm.
GEN
INFO
This tool is necessary for checking ignition timing.
YM-4019, 90890-04019Valve spring compressor
This tool is needed to remove and install the valve
assemblies.
YM-91042, 90890-04086Clutch holding tool
This tool is used to hold the clutch when removing or
installing the clutch boss securing nut.
YM-4111, 90890-04111
YM-4116, 90890-04116
YM-4112, 90890-04112
YM-4117, 90890-04117
YM-4113, 90890-04113
YM-4118, 90890-04118
Valve guide remover
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to remove and install the valve
guide.
Valve guide installer
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to install the valve guide.
Valve guide reamer
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to rebore the new valve guide.
1 - 8
Page 25
SPECIAL TOOLS
Part numberTool name/How to useIllustration
YM-04141, 90890-04141Rotor puller
This tool is used to remove the flywheel magneto.
YM-34487
90890-06754
ACC-QUICK-GS-KT
90890-85505
Dynamic spark tester
Ignition checker
This instrument is necessary for checking the ignition
system components.
Quick gasket
YAMAHA Bond No. 1215
This sealant (Bond) is used for crankcase mating sur-
face, etc.
GEN
INFO
1 - 9
Page 26
CONTROL FUNCTIONS
EC150000
CONTROL FUNCTIONS
MAIN SWITCH
Functions of the respective switch positions
are as follows:
ON:
The engine can be started only at this position.
OFF:
All electrical circuits are switched off.
Main switch indicator light
The main switch 1 is equipped with an indicator light 2 to avoid forgetting to turn it off. This
light functions as follows.
• It lights up with the main switch “ON”.
• It goes out when the engine increases its
speed after being started.
• It lights up again when the engine is stopped.
GEN
INFO
OTE:
If the indicator light will not light up with the
main switch “ON”, it shows a lack of the battery
voltage. Recharge the battery. If the engine is
kick started, turn off the light switch.
ENGINE STOP SWITCH
The engine stop switch 1 is located on the left
handlebar. Continue pushing the engine stop
switch till the engine comes to a stop.
START SWITCH
The start switch 1 is located on the right handlebar. Push this switch to crank the engine
with the starter.
1 - 10
Page 27
CONTROL FUNCTIONS
EC152000
CLUTCH LEVER
The clutch lever 1 is located on the left handlebar; it disengages or engages the clutch.
Pull the clutch lever to the handlebar to disengage the clutch, and release the lever to
engage the clutch. The lever should be pulled
rapidly and released slowly for smooth starts.
EC153000
SHIFT PEDAL
The gear ratios of the constant-mesh 5 speed
transmission are ideally spaced. The gears
can be shifted by using the shift pedal 1 on
the left side of the engine.
GEN
INFO
1
KICKSTARTER CRANK
Rotate the kickstarter crank 1 away from the
engine. Push the starter down lightly with your
foot until the gears engage, then kick smoothly
and forcefully to start the engine. This model
has a primary kickstarter crank so the engine
can be started in any gear if the clutch is disengaged. In normal practices, however, shift to
neutral before starting.
EC155001
THROTTLE GRIP
The throttle grip 1 is located on the right handlebar; it accelerates or decelerates the
engine. For acceleration, turn the grip toward
you; for deceleration, turn it away from you.
EC156000
FRONT BRAKE LEVER
The front brake lever 1 is located on the right
handlebar. Pull it toward the handlebar to activate the front brake.
1 - 11
Page 28
CONTROL FUNCTIONS
EC157000
REAR BRAKE PEDAL
The rear brake pedal 1 is located on the right
side of the machine. Press down on the brake
pedal to activate the rear brake.
FUEL COCK
The fuel cock supplies fuel from the tank to
carburetor and also filters the fuel. The fuel
cock has three positions:
OFF:With the lever in this position, fuel will not
flow. Always return the lever to this position when the engine is not running.
ON: With the lever in this position fuel flows to
the carburetor. Normal riding is done with
the lever in this position.
RES:With the lever in this position fuel flows to
the carburetor from the reserve section of
the fuel tank after the main supply of the
fuel has been depleted. Normal riding is
possible with the lever is in this position,
but it is recommended to add fuel as
soon as possible.
GEN
INFO
COLD STARTER KNOB
When cold, the engine requires a richer air-fuel
mixture for starting. A separate starter circuit,
which is controlled by the cold starter knob 1,
supplies this mixture. Pull the cold starter knob
out to open the circuit for starting. When the
engine has warmed up, push it in to close the
circuit.
HOT STARTER LEVER
The hot starter lever 1 is used when starting a
warm engine.
Use the hot starter lever when starting the
engine again immediately after it was stopped
(the engine is still warm). Pulling the hot starter
lever injects secondary air to thin the air-fuel
mixture temporarily, allowing the engine to be
started more easily.
1 - 12
Page 29
CONTROL FUNCTIONS
LIGHT SWITCH
The light switch 1 is located on the handlebar.
EC15F000
VALVE JOINT
This valve joint 1 prevents fuel from flowing
out and is installed to the fuel tank breather
hose.
CAUTION:
In this installation, make sure the arrow
faces the fuel tank and also downward.
GEN
INFO
1
SPARK PLUG WRENCH
This spark plug wrench 1 is used to remove
and install the spark plug.
1
NIPPLE WRENCH
This nipple wrench 1 is used to tighten the
spoke.
1 - 13
Page 30
GEN
FUEL
FUEL
Always use the recommended fuel as stated
below. Also, be sure to use new gasoline the
day of a race.
Recommended fuel:
Except for ZA:
Premium unleaded gasoline
only with a research octane
number of 95 or higher.
For ZA:
Premium gasoline
CAUTION:
Use only unleaded gasoline. The use of
leaded gasoline will cause severe damage
to the engine internal parts such as valves,
piston rings, and exhaust system, etc.
INFO
OTE:
If knocking or pinging occurs, use a different
brand of gasoline or higher octane grade.
WARNING
• For refueling, be sure to stop the engine
and use enough care not to spill any fuel.
Also be sure to avoid refueling close to a
fire.
• Refuel after the engine, exhaust pipe, etc.
have cooled off.
1 - 14
Page 31
STARTING AND BREAK-IN
STARTING AND BREAK-IN
WARNING
Never start or run the engine in a closed
area. The exhaust fumes are poisonous;
they can cause loss of consciousness and
death in a very short time. Always operate
the machine in a well-ventilated area.
CAUTION:
• The carburetor on this machine has a
built-in accelerator pump. Therefore,
when starting the engine, do not operate
the throttle or the spark plug will foul.
• Unlike a two-stroke engine, this engine
cannot be kick started when the throttle is
open because the kickstarter may kick
back. Also, if the throttle is open the air/
fuel mixture may be too lean for the
engine to start.
• Before starting the machine, perform the
checks in the pre-operation check list.
GEN
INFO
AIR FILTER MAINTENANCE
According to “AIR FILTER CLEANING” section
in the CHAPTER 3, apply the foam-air-filter oil
or its equivalent to the element. (Excess oil in
the element may adversely affect engine starting.)
STARTING A COLD ENGINE
OTE:
This model is equipped with an ignition circuit
cut-off system. The engine can be started
under the following conditions.
• When the transmission is in neutral.
• When the clutch is disengaged with the
transmission in any position. However, it is
recommended to shift into neutral before
starting the engine.
1. Inspect the coolant level.
2. Turn the fuel cock to “ON”.
3. Push on the main switch to “ON”.
4. Shift the transmission into neutral.
5. Fully open the cold starter knob 1.
6. Start the engine by pushing the start switch
or by kicking the kickstarter crank.
1 - 15
Page 32
STARTING AND BREAK-IN
OTE:
If the engine fails to start by pushing the start
switch, release the switch, wait a few seconds,
and then try again. Each starting attempt
should be as short as possible to preserve the
battery. Do not crank the engine more than
10 seconds on any one attempt. If the engine
does not start with the starter motor, try using
the kickstarter crank.
WARNING
• If the starter motor will not turn when
pushing the start switch, stop pushing it
immediately and kick start the engine in
order to avoid the load on the motor.
• Do not open the throttle while kicking the
kickstarter crank. Otherwise, the kickstarter crank may kick back.
GEN
INFO
7. Return the cold starter knob to its original
position and run the engine at 3,000 ~
5,000 r/min for 1 or 2 minutes.
OTE:
Since this model is equipped with an accelerator pump, if the engine is raced (the throttle
opened and closed), the air/fuel mixture will be
too rich and the engine may stall. Also unlike a
two-stroke engine, this model can idle.
CAUTION:
Do not warm up the engine for extended
periods of time.
1 - 16
Page 33
STARTING AND BREAK-IN
STARTING A WARM ENGINE
Do not operate the cold starter knob and throttle. Pull the hot starter lever 1 and start the
engine by pushing the start switch or by kicking the kickstarter crank forcefully with a firm
stroke.
As soon as the engine starts, Release the hot
starter lever to close the air passage.
Restarting an engine after a fall
Pull the hot starter lever and start the engine.
As soon as the engine starts, Release the hot
starter lever to close the air passage.
The engine fails to start
Pull the hot starter lever all the way out and
while holding the lever, kick the kickstarter
crank 10 to 20 times to clear the engine.
Then, restart the engine.
Refer to “Restarting an engine after a fall”.
Air temperature = less than
5 °C (41 °F)
Air temperature = more
than 5 °C (41 °F)
Air temperature (normal temperature) = between 5 °C
(41 °F) and 25 °C (77 °F)
Air temperature = more
Starting a cold engine
than 25 °C (77 °F)
Starting an engine after a long
period of time
Restarting a warm engineNoneOFFON
Restarting an engine after a fallNoneOFFON
* Operate the throttle grip before kick starting.
GEN
INFO
Throttle
grip
operation*
Open 3
or 4 times
NoneONOFF
NoneON/OFFOFF
NoneOFFOFF
NoneONOFF
Cold
starter
knob
ONOFF
Hot
starter
lever
CAUTION:
Observe the following break-in procedures
during initial operation to ensure optimum
performance and avoid engine damage.
1 - 17
Page 34
STARTING AND BREAK-IN
BREAK-IN PROCEDURES
1. Before starting the engine, fill the fuel tank
with the fuel.
2. Perform the pre-operation checks on the
machine.
3. Start and warm up the engine. Check the
idle speed, and check the operation of the
controls and the engine stop switch. Then,
restart the engine and check its operation
within no more than 5 minutes after it is
restarted.
4. Operate the machine in the lower gears at
moderate throttle openings for five to eight
minutes.
5. Check how the engine runs when the
machine is ridden with the throttle 1/4 to 1/2
open (low to medium speed) for about one
hour.
6. Restart the engine and check the operation
of the machine throughout its entire operating range. Restart the machine and operate it for about 10 to 15 more minutes. The
machine will now be ready to race.
GEN
INFO
CAUTION:
• After the break-in or before each race,
you must check the entire machine for
loose fittings and fasteners as per
“TORQUE-CHECK POINTS”.
Tighten all such fasteners as required.
• When any of the following parts have
been replaced, they must be broken in.
CYLINDER AND CRANKSHAFT:
About one hour of break-in operation is
necessary.
PISTON, RING, VALVES, CAMSHAFTS
AND GEARS:
These parts require about 30 minutes of
break-in operation at half-throttle or less.
Observe the condition of the engine carefully during operation.
1 - 18
Page 35
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
GEN
INFO
Frame construction
Combined seat and fuel tank
Exhaust system
Engine mounting
SteeringSteering stem to
handlebar
SuspensionFrontSteering stem to front
fork
RearFor link type
RearInstallation of rear
shock absorber
Frame to rear frame
Fuel tank to frame
Silencer to rear frame
Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Front fork to upper bracket
Front fork to lower bracket
Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Rear shock absorber to frame
RearInstallation of swing-
arm
WheelInstallation of wheelFront
Rear
BrakeFront
Rear
Fuel system
Lubrication system
Tightening of pivot shaft
Tightening of wheel axle
Tightening of axle holder
Tightening of wheel axle
Wheel to rear wheel sprocket
Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Fuel tank to fuel cock
Tightening of oil hose clamp
OTE:
Concerning the tightening torque, refer to
“MAINTENANCE SPECIFICATIONS” section
in the CHAPTER 2.
1 - 19
Page 36
CLEANING AND STORAGE
EC1B0000
CLEANING AND STORAGE
EC1B1000
CLEANING
Frequent cleaning of your machine will
enhance its appearance, maintain good overall
performance, and extend the life of many components.
1. Before washing the machine, block off the
end of the exhaust pipe to prevent water
from entering. A plastic bag secured with a
rubber band may be used for this purpose.
2. If the engine is excessively greasy, apply
some degreaser to it with a paint brush. Do
not apply degreaser to the chain, sprockets, or wheel axles.
3. Rinse the dirt and degreaser off with a gar-
den hose; use only enough pressure to do
the job.
GEN
INFO
CAUTION:
Excessive hose pressure may cause water
seepage and contamination of wheel bearings, front forks, brakes and transmission
seals. Many expensive repair bills have
resulted from improper high pressure
detergent applications such as those available in coin-operated car washers.
4. After the majority of the dirt has been
hosed off, wash all surfaces with warm
water and a mild detergent. Use an old
toothbrush to clean hard-to-reach places.
5. Rinse the machine off immediately with
clean water, and dry all surfaces with a soft
towel or cloth.
6. Immediately after washing, remove excess
water from the chain with a paper towel
and lubricate the chain to prevent rust.
7. Clean the seat with a vinyl upholstery
cleaner to keep the cover pliable and
glossy.
8. Automotive wax may be applied to all
painted or chromed surfaces. Avoid combination cleaner-waxes, as they may contain
abrasives.
9. After completing the above, start the
engine and allow it to idle for several minutes.
1 - 20
Page 37
CLEANING AND STORAGE
EC1B2001
STORAGE
If your machine is to be stored for 60 days or
more, some preventive measures must be
taken to avoid deterioration. After cleaning the
machine thoroughly, prepare it for storage as
follows:
1. Drain the fuel tank, fuel lines, and the car-
buretor float bowl.
2. Remove the spark plug, pour a tablespoon
of SAE 10W-30 motor oil in the spark plug
hole, and reinstall the plug. With the engine
stop switch pushed in, kick the engine over
several times to coat the cylinder walls with
oil.
3. Remove the drive chain, clean it thoroughly
with solvent, and lubricate it. Reinstall the
chain or store it in a plastic bag tied to the
frame.
4. Lubricate all control cables.
5. Block the frame up to raise the wheels off
the ground.
6. Tie a plastic bag over the exhaust pipe out-
let to prevent moisture from entering.
7. If the machine is to be stored in a humid or
salt-air environment, coat all exposed
metal surfaces with a film of light oil. Do not
apply oil to rubber parts or the seat cover.
GEN
INFO
OTE:
Make any necessary repairs before the
machine is stored.
1 - 21
Page 38
2
GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name:WR250FR (USA)
WR250F (EUROPE)
WR250F(R) (CDN, AUS, NZ, ZA)
Model code number:5UM1 (USA)
5UM2 (EUROPE)
5UM4 (CDN, AUS, NZ, ZA)
Dimensions:
Overall length2,165 mm (85.2 in)
Overall width827 mm (32.6 in)
Overall height1,303 mm (51.3 in)
Seat height998 mm (39.3 in)
Wheelbase1,475 mm (58.1 in)
Minimum ground clearance382 mm (15.0 in)
Starting systemKick and electric starter
Lubrication system:Dry sump
Oil type or grade:
Engine oil(For USA and CDN)
At 5 °C (40 °F) or higher È
Yamalube 4 (20W-40) or SAE 20W-40 type
SG motor oil
(Non-Friction modified)
At 15 °C (60 °F) or lower É
Yamalube 4 (10W-30) or SAE 10W-30 type
SG motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
-20-4-10140301050206830864050
˚CTemp.
(Non-Friction modified)
(Except for USA and CDN)
10W-30
10W-40
15W-40
20W-40
20W-50
API “SG” or higher grade
3
(8.76 Imp oz, 8.42 US oz)
SPEC
104
122
˚F
2 - 1
Page 39
GENERAL SPECIFICATIONS
Oil capacity:
Engine oil
Periodic oil change1.2 L (1.06 Imp qt, 1.27 US qt)
With oil filter replacement1.3 L (1.14 Imp qt, 1.37 US qt)
Total amount1.4 L (1.23 Imp qt, 1.48 US qt)
Coolant capacity (including all routes):1.3 L (1.14 Imp qt, 1.37 US qt)
Air filter:Wet type element
Fuel:
TypePremium unleaded gasoline only with a
research octane number of 95 or higher.
(Except for ZA)
Premium gasoline (For ZA)
Tank capacity10 L (2.2 Imp gal, 2.64 US gal)
Reserve1.2 L (0.26 Imp gal, 0.32 US gal)
Shifter typeCam drum and guide bar---Guide bar bending limit----0.05 mm
Kickstarter:
TypeKick and ratchet type----
Carburetor:
Type/manufacturerFCR-MX37/KEIHIN←
I. D. mark5UM1 005UM2 10
Main jet(M.J)#185#172
Main air jet(M.A.J)ø2.0←
Jet needle(J.N)OBDVS-4OBELP-4
Cutaway(C.A)1.5←
Pilot jet(P.J)#40←
Pilot air jet(P.A.J)#75←
Pilot outlet(P.O)ø0.9←
Pilot screw (example)(P.S)21-7/8
Bypass(B.P)ø1.0←
Valve seat size(V.S)ø3.8←
Starter jet(G.S)#72←
Leak jet(Acc.P)#90←
Float height(F.H)8 mm (0.31 in)←
Engine idle speed1,900 ~ 2,100 r/min←
Intake vacuum26.7 ~ 32.0 kPa
(200 ~ 240 mmHg,
7.87 ~ 9.45 inHg)
Hot starter lever free play3 ~ 6 mm
(0.12 ~ 0.24 in)
USA
SPEC
(0.106 in)
(0.004 in)
(1.42 in)
----
----
(0.002 in)
EUROPE, CDN,
ZA, AUS, NZ
←
←
2 - 8
Page 46
MAINTENANCE SPECIFICATIONS
ItemStandardLimit
Lubrication system:
Oil filter typePaper type---Oil pump typeTrochoid type---Tip clearance0.12 mm or less
(0.0047 in or less)
Side clearance0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)
Housing and rotor clearance0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)
Cooling:
Radiator core size
Width117.8 mm (4.6 in)---Height220 mm (8.7 in)----
Thickness32 mm (1.26 in)---Radiator cap opening pressure110 kPa (1.1 kg/cm
Radiator capacity (total)0.6 L (0.53 Imp qt, 0.63 US qt)---Water pump
Master cylinder inside dia.11.0 mm (0.433 in)---Caliper cylinder inside dia.25.4 mm (1.000 in) × 1---Brake fluid typeDOT #4----
Brake lever and brake pedal:
Brake lever position95 mm (3.74 in)---Brake pedal height
(vertical height above footrest top)
Clutch lever free play (lever end)8 ~ 13 mm (0.31 ~ 0.51 in)---Throttle grip free play3 ~ 5 mm (0.12 ~ 0.20 in)----
5 mm (0.20 in)----
SPEC
(0.08 in)
(0.08 in)
(5.91 in)
250 × 2.5 mm
(9.84
(0.04 in)
245 × 3.5 mm
(9.65
(0.006 in)
(0.04 in)
×
0.10 in)
×
0.14 in)
2 - 13
Page 51
MAINTENANCE SPECIFICATIONS
SPEC
Part to be tightenedThread sizeQ’ty
Upper bracket and outer tubeM8 × 1.254232.317
Lower bracket and outer tubeM8 × 1.254202.014
Upper bracket and steering stemM24 × 1.0114514.5105
Handlebar upper holder and upper bracketM8 × 1.254282.820
Steering stem and steering ring nutM28 × 1.01Refer to NOTE.
Front fork and front fork cap boltM48 × 1.02303.022
Front fork and base valveM30 × 1.02555.540
Front fork cap bolt and damper rodM12 × 1.252292.921
Front fork bleed screw and front fork cap boltM5 × 0.8210.10.7
Front fork and front fork protectorM6 × 1.06101.07.2
Front fork and brake hose holderM6 × 1.02101.07.2
Front fork and brake hose cover (M8)M8 × 1.251161.611
(M6)M6 × 1.0170.75.1
Throttle grip capM5 × 0.8240.42.9
Front brake master cylinderM6 × 1.0290.96.5
Brake lever mounting boltM6 × 1.0160.64.3
Brake lever mounting nutM6 × 1.0160.64.3
Brake lever position locknutM6 × 1.0150.53.6
Front brake hose guideM5 × 0.8240.42.9
Clutch lever holderM5 × 0.8240.42.9
Hot starter lever holderM5 × 0.8240.42.9
Hot starter lever mounting nutM5 × 0.8120.21.4
Light switchM4 × 0.7220.21.4
Front brake master cylinder capM4 × 0.7220.21.4
Front brake hose union boltM10 × 1.252303.022
Front brake caliperM8 × 1.252232.317
Pad pin plugM10 × 1.0230.32.2
Front brake caliper and pad pinM10 × 1.01181.813
Rear brake caliper and pad pinM10 × 1.01181.813
Brake caliper and bleed screwM8 × 1.25260.64.3
Front wheel axle and axle nutM16 × 1.5110510.575
Front wheel axle holderM8 × 1.254232.317
Front brake discM6 × 1.06121.28.7
Rear brake discM6 × 1.06141.410
Brake pedalM8 × 1.251262.619
Rear brake master cylinder M6 × 1.02111.18.0
Rear brake master cylinder capM4 × 0.7220.21.4
Rear brake hose union boltM10 × 1.252303.022
Rear wheel axle and axle nut M20 × 1.5112512.590
Tightening torque
Nmm·kgft·lb
OTE:
1. First, tighten the steering nut approximately 38 Nm (3.8 m • kg, 27 ft • lb) by using the steering
nut wrench, then loosen the steering nut one turn.
2. Retighten the steering nut 7 Nm (0.7 m • kg, 5.1 ft • lb).
Model/manufacturer5UL-00/DENSO---Minimum spark gap6 mm (0.24 in)---Primary coil resistance0.08 ~ 0.10 Ω at 20 °C (68 °F)----
Secondary coil resistance4.6 ~ 6.8 kΩ at 20 °C (68 °F)----
Charging system:
System typeAC magneto---Model/manufacturer5UM-00/YAMAHA---Normal output14 V/120 W at 5,000 r/min---Charging coil resistance (color)0.288 ~ 0.432 Ω at 20 °C (68 °F)
(White – Ground)
Lighting coil resistance (color)0.224 ~ 0.336 Ω at 20 °C (68 °F)
(Yellow – Ground)
Rectifier/regulator:
Regulator typeSemiconductor short circuit---Model/manufactureSH712AA/SHINDENGEN---Regulated voltage (AC)13.0 ~ 14.0 V---Regulated voltage (DC)14.1 ~ 14.9 V---Rectifier capacity (AC)12 A---Rectifier capacity (DC)8 A----
Electric starting system:
TypeConstant mesh---Starter motor:
Model/manufacturer5UM00/YAMAHA---Operation voltage12 V---Output0.35 kW---Armature coil resistance0.0189 ~ 0.0231 Ω at 20 °C (68 °F)----
Brush overall length7 mm (0.28 in)3.5 mm (0.14 in)
Brush quantity2 pcs.---Spring force3.92 ~ 5.88 N
(400 ~ 600 g, 14.1 ~ 21.2 oz)
Commutator diameter17.6 mm (0.69 in)16.6 mm (0.65 in)
Mica undercut (depth)1.5 mm (0.06 in)----
SPEC
----
----
----
----
2 - 17
Page 55
MAINTENANCE SPECIFICATIONS
ItemStandardLimit
Starter relay:
Model/manufacturer2768090-A/JIDECO---Amperage rating180 A---Coil winding resistance4.2 ~ 4.6 Ω at 20 °C (68 °F)----
Starting circuit cut-off relay:
Model/manufacturerACM33221 M06/MATSUSHITA---Coil winding resistance75.69 ~ 92.51 Ω at 20 °C (68 °F)----
This chart specifies torque for standard fasteners with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sections of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fashion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Components should be at room temperature.
A
(Nut)
B
(Bolt)
TORQUE
SPECIFICATION
Nmm•kgft•lb
SPEC
A: Distance between flats
B: Outside thread diameter
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm
EC230000
6 mm
8 mm
10 mm
12 mm
14 mm
16 mm
6
15
30
55
85
130
0.6
1.5
3.0
5.5
8.5
13
4.3
11
22
40
61
94
DEFINITION OF UNITS
UnitReadDefinitionMeasure
mm
cm
millimeter
centimeter
kgkilogram10
NNewton1 kg × m/sec
Nm
m • kg
Newton meter
Meter kilogram
PaPascalN/m
N/mmNewton per millimeterN/mmSpring rate
L
cm
3
Liter
Cubic centimeter
r/minRevolution per minute—Engine speed
-3
10
meter
-2
10
meter
3
gramWeight
2
Force
N × m
m × kg
2
—
—
Length
Length
Torque
Torque
Pressure
Volume or capacity
Volume or capacity
2 - 19
Page 57
EC240000
CABLE ROUTING DIAGRAM
Fuel tank breather hose
1
Oil tank breather hose
2
Clamp
3
Diode
4
Wire harness
5
Hot starter cable
6
Throttle position sensor lead
7
Neutral switch lead
8
Oil hose
9
Hose guide
0
AC magneto lead
A
Cylinder head breather hose
B
Starter motor lead
C
Clutch cable
D
Radiator hose 1
E
Radiator pipe (radiator hose 4)
F
CABLE ROUTING DIAGRAM
Cable guide
G
Negative battery lead
H
Light switch lead
I
Brake hose
J
Carburetor breather hose
K
Carburetor overflow hose
L
Coolant reservoir breather
M
hose
SPEC
2 - 20
Page 58
CABLE ROUTING DIAGRAM
SPEC
Insert the fuel tank breather hose into the hole in
È
the steering stem cap.
Pass the oil tank breather hose on the outside of
É
the AC magneto lead, neutral switch lead, light
switch lead, wire harness, starter motor lead, negative battery lead and cylinder head breather
hose.
Fasten the diode and rectifier/regulator lead, with
Ê
the diode at its white tape and the rectifier/regulator lead at its protecting tube.
Fasten the wire harness, starter motor lead and
Ë
negative battery lead so that the plastic locking tie
ends do not contact the ignition coil lead.
Fasten the wire harness, rectifier/regulator lead,
Ì
coolant reservoir hose, hot starter cable, negative
battery lead and starter motor lead.
Fasten the wire harness, negative battery lead,
Í
starter motor lead, rectifier/regulator lead and
coolant reservoir hose at the white tape for the
negative battery lead.
2 - 21
Page 59
CABLE ROUTING DIAGRAM
SPEC
Fasten the wire harness at its white tape.
Î
Fasten the wire harness, throttle position sensor
Ï
lead (in the wire harness), starter motor lead and
negative battery lead.
Make sure that the throttle position sensor coupler
Ð
does not go outside the chassis.
Fasten the throttle position sensor lead.
Ñ
Pass the carburetor breather hoses, carburetor
Ò
overflow hose and coolant reservoir breather hose
between the connecting rod and cross tube
(frame).
Fasten the neutral switch lead and oil hose
Ó
together with the plastic locking ties and cut off the
tie ends.
Pass the cylinder head breather hose through the
Ô
hose guide.
Fasten the neutral switch lead.
Õ
Fasten the neutral switch lead and AC magneto
Ö
lead.
2 - 22
Page 60
CABLE ROUTING DIAGRAM
SPEC
Pass the cylinder head breather hose on the
×
inside of the radiator hose 1 and on the outside of
the radiator pipe (radiator hose 4). Make sure that
the cylinder head breather hose does not go forward of the chassis.
Pass the starter motor lead in front of the radiator
Ø
hose 4.
Pass the clutch cable through the cable guide.
Ù
Pass the wire harness on the outside of the neu-
Ú
tral switch lead and AC magneto lead.
Fit the brake hose into the guides on the protector.
Û
Pass the wire harness, clutch cable and light
Ü
switch lead through the cable guide.
Fasten the AC magneto lead, neutral switch lead
Ý
and light switch lead to the cable guide at their
protecting tube with a plastic locking tie and cut off
the tie end.
Pass the carburetor breather hoses, carburetor
Þ
overflow hose and coolant reservoir breather hose
so that the hoses do not contact the rear shock
absorber.
2 - 23
Page 61
CABLE ROUTING DIAGRAM
SPEC
Hot starter cable
1
Cable guide
2
Throttle cable (return)
3
Throttle cable (pull)
4
Ignition coil
5
Coolant reservoir breather
6
hose
Rectifier/regulator
7
Coolant reservoir hose
8
Rectifier/regulator lead
9
Clamp
0
CDI unit lead
A
CDI unit
B
CDI unit band
C
CDI unit stay
D
Rectifier/regulator bracket
E
Pass the throttle cables and
È
hot starter cable through the
cable guides.
Pass the throttle cables and
É
hot starter cable between the
radiator and frame, then under
the radiator mounting boss.
Pass the throttle cables on the
Ê
outside of the ignition coil.
Pass the carburetor breather
Ë
hose (of the throttle cable
cover) through the hose holder.
2 - 24
Page 62
CABLE ROUTING DIAGRAM
Fasten the coolant reservoir breather hose and
Ì
carburetor breather hoses together.
Fasten the CDI unit lead.
Í
Insert the CDI unit band over the CDI unit stay as
Î
far as possible.
Fasten the rectifier/regulator lead to the rectifier/
Ï
regulator bracket with a plastic locking tie and cut
off the tie end.
SPEC
2 - 25
Page 63
CABLE ROUTING DIAGRAM
SPEC
Brake master cylinder
1
Brake hose holder
2
Brake hose
3
Install the brake hose so that its pipe portion
È
directs as shown and lightly touches the projection
on the brake caliper.
Pass the brake hose into the brake hose holders.
É
If the brake hose contacts the spring (rear shock
Ê
absorber), correct its twist.
Install the brake hose so that its pipe portion
Ë
directs as shown and lightly touches the projection
on the brake master cylinder.
2 - 26
Page 64
CABLE ROUTING DIAGRAM
SPEC
Starter motor lead
1
Negative battery lead
2
Wire harness
3
Clamp
4
Taillight lead
5
Coolant reservoir breather hose
6
Coolant reservoir hose
7
Positive battery lead
8
Starting circuit cut-off relay
9
Battery
0
Position the starter motor lead, negative battery
È
lead and wire harness in the tank damper slit.
Fasten the wire harness.
É
Do not allow the taillight lead to slacken.
Ê
Fasten the coolant reservoir breather hose, cool-
Ë
ant reservoir hose and rectifier/regulator lead.
Fasten the coolant reservoir breather hose and
Ì
coolant reservoir hose.
Pass the coolant reservoir hose on the outside of
Í
the coolant reservoir breather hose.
2 - 27
Page 65
CABLE ROUTING DIAGRAM
SPEC
Throttle cable
1
Brake hose
2
Clamp
3
Light switch lead
4
Hot starter cable
5
Clutch cable
6
Hose guide
7
Clutch switch lead
8
Engine stop switch lead
9
Trip meter cable
0
Main switch lead
A
Trip meter
B
Main switch
C
Light switch
D
Start switch lead
E
Fasten the start switch lead
È
and light switch lead.
Fasten the engine stop switch
É
lead and clutch switch lead.
Pass the brake hose through
Ê
the hose guide.
Pass the start switch lead in
Ë
front of the main switch lead.
Fasten the start switch lead.
Ì
Pass the hot starter cable,
Í
clutch cable and light switch
lead between the upper
bracket and coupler bracket.
Pass the throttle cables
Î
between the upper bracket and
trip meter.
2 - 28
Page 66
INSP
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the
required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
ADJ
race
Every third
500 km)
Item
ENGINE OIL
Replace
Inspect
VALVES
Check the valve clearancesThe engine must be cold.
Inspect
Replace
VALVE SPRINGS
InspectCheck the free length and
Replace
VALVE LIFTERS
InspectCheck for scratches and
Replace
CAMSHAFTSInspect the camshaft sur-
Inspect
Replace
TIMING CHAIN SPROCKETS, TIMING
CHAIN
InspectCheck for wear on the
Replace
PISTON
InspectInspect crack
Clean
Replace
PISTON RING
InspectCheck ring end gap
Replace
PISTON PIN
Inspect
Replace
CYLINDER HEADInspect carbon deposits
Inspect and clean
CYLINDER
Inspect and cleanInspect score marks
Replace
CLUTCHInspect housing, friction
Inspect and adjust
Replace
TRANSMISSION
Inspect
Replace bearing
After
break-in
Every
(or
Every fifth
(or
1,000 km)
As required
Remarks
Check the valve seats
and valve stems for wear.
the tilt.
wear.
face.
Inspect the decompression system.
teeth and for damage.
Inspect carbon deposits
and eliminate them.
and eliminate them.
Change gasket
Inspect wear
plate, clutch plate and
spring
3 - 1
Page 67
MAINTENANCE INTERVALS
INSP
ADJ
race
Every third
500 km)
Item
SHIFT FORK, SHIFT CAM, GUIDE BAR
InspectInspect wear
ROTOR NUT
Retighten
EXHAUST PIPE, SILENCER,
PROTECTOR
Inspect and retighten
Clean
Replace* Whichever comes first
*SPARK ARRESTER
Clean
CRANK
Inspect and clean
CARBURETOR
Inspect, adjust and clean
SPARK PLUG
Inspect and clean
Replace
DRIVE CHAINUse chain lube
Lubricate, slack, alignment
Replace
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolantEvery two years
Inspect hoses
OUTSIDE NUTS AND BOLTSRefer to “STARTING
Retighten
AIR FILTER
Clean and lubricateUse foam air-filter oil or
Replace
OIL FILTER
Replace
OIL STRAINER (frame)
Clean
FRAME
Clean and inspect
FUEL TANK, COCK
Clean and inspect
BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper
bolts, master cylinder bolts and union
bolts
Replace pads
Replace brake fluidEvery one year
After
break-in
Every
(or
Every fifth
(or
1,000 km)
As re-
quired
(Every six
months)
Remarks
Chain slack:
40 ~ 50 mm (1.6 ~ 2.0 in)
AND BREAK-IN” section
in the CHAPTER 1.
equivalent oil
3
3 - 2
Page 68
MAINTENANCE INTERVALS
INSP
ADJ
race
Every third
500 km)
Item
FRONT FORKS
Inspect and adjust
Replace oilSuspension oil “01”
Replace oil seal
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lubeLithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
Retighten
DRIVE CHAIN GUIDE AND ROLLERS
Inspect
SWINGARMMolybdenum disulfide
Inspect, lube and retighten
RELAY ARM, CONNECTING RODMolybdenum disulfide
Inspect, lube and retighten
STEERING HEAD
Inspect free play and retighten
Clean and lubeLithium base grease
Replace bearing
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
LubricateLithium base grease
THROTTLE, CONTROL CABLEYamaha cable lube or
Check routing and connection
Lubricate
Inspect and clean (throttle cable)
HOT STARTER, CLUTCH LEVER
Inspect free play
BATTERY
Check terminal for looseness and
corrosion
After
break-in
Every
(or
Every fifth
(or
1,000 km)
As re-
quired
(After
rain ride)
Remarks
Molybdenum disulfide
grease
grease
grease
SAE 10W-30 motor oil
Inspect dirt and wear on
the throttle cable on the
carburetor side.
*marked: For USA
3 - 3
Page 69
INSP
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
ItemRoutinePage
Coolant
Fuel
Engine oil
Gear shifter and clutch
Throttle grip/Housing
BrakesCheck the play of front brake and effect of front and rear brake.P.3-25 ~ 31
Drive chain
Wheels
Steering
Front forks and rear shock
absorber
Cables (wires)
Exhaust pipe
Rear wheel sprocketCheck that the rear wheel sprocket tightening bolt is not loose.P.3-32
LubricationCheck for smooth operation. Lubricate if necessary.P.3-46
Bolts and nutsCheck the chassis and engine for loose bolts and nuts.P.1-19
Lead connectors
Settings
Check that coolant is filled up to the radiator cap.
Check the cooling system for leakage.
Check that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.
Check that the oil level is correct. Check the crankcase and
frame oil line for leakage.
Check that gears can be shifted correctly in order and that the
clutch operates smoothly.
Check that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.
Check drive chain slack and alignment. Check that the drive
chain is lubricated properly.
Check for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.
Check that the handlebar can be turned smoothly and have no
excessive play.
Check that they operate smoothly and there is no oil leakage.P.3-35 ~ 42
Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or
when the front forks travel up and down.
Check that the exhaust pipe is tightly mounted and has no
cracks.
Check that the AC magneto, CDI unit, and ignition coil are connected tightly.
Is the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?
ADJ
P.3-5 ~ 9
P.1-14
P.3-14 ~ 18
P.3-9 ~ 10
P.3-10 ~ 11
P.3-32 ~ 35
P.3-43 ~ 44
P.3-44 ~ 45
—
P.4-3 ~ 4
P.1-6
P.7-1 ~ 22
3 - 4
Page 70
ENGINE/COOLANT LEVEL INSPECTION/
COOLANT REPLACEMENT
EC350000
ENGINE
COOLANT LEVEL INSPECTION
WARNING
Do not remove the radiator cap 1, drain
bolt and hoses when the engine and radiator are hot. Scalding hot fluid and steam
may be blown out under pressure, which
could cause serious injury.
When the engine has cooled, place a thick
towel over the radiator cap, slowly rotate
the cap counterclockwise to the detent.
This procedure allows any residual pressure to escape. When the hissing sound
has stopped, press down on the cap while
turning counterclockwise and remove it.
INSP
ADJ
LOW
FULL
COOLANT
a
b
CAUTION:
Hard water or salt water is harmful to the
engine parts. You may use distilled water, if
you can’t get soft water.
1. Place the machine on a level place, and
hold it in an upright position.
2. Inspect:
• Coolant level
Coolant level should be between the
maximum a and minimum b marks.
Coolant level is below the “LOW” level
line → Add soft water (tap water) up to
the proper level.
3. Start the engine and let it warm up for several minutes.
4. Turn off the engine and check the coolant
level again.
OTE:
Before checking the coolant level, wait a few
minutes until the coolant settles.
COOLANT REPLACEMENT
WARNING
Do not remove the radiator cap when the
engine is hot.
3 - 5
Page 71
1
LOW
FULL
COOLANT
COOLANT REPLACEMENT
CAUTION:
Take care so that coolant does not splash
on painted surfaces. If it splashes, wash it
away with water.
1. Place a container under the engine.
2. Remove:
• Seat
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
3. Disconnect:
• Coolant reservoir hose 1
Drain the coolant completely.
4. Connect:
• Coolant reservoir hose
INSP
ADJ
5. Remove:
• Engine guard 1
• Coolant drain bolt 2
6. Remove:
• Radiator cap
Drain the coolant completely.
7. Clean:
• Cooling system
Thoroughly flush the cooling system with
clean tap water.
8. Install:
• Copper washer
New
• Coolant drain bolt
T
10 Nm (1.0 m · kg, 7.2 ft · lb)
.
R
.
• Engine guard
• Bolt [engine guard (front)]
T
34 Nm (3.4 m · kg, 24 ft · lb)
.
R
.
• Bolt [engine guard (rear)]
T
23 Nm (2.3 m · kg, 17 ft · lb)
.
R
.
3 - 6
Page 72
COOLANT REPLACEMENT
9. Fill:
• Radiator
• Engine
To specified level.
Recommended coolant:
High quality ethylene glycol
anti-freeze containing
anti-corrosion for
aluminum engine
Coolant 1 and water
(soft water) 2 mixing ratio:
50%/50%
Coolant capacity:
1.3 L (1.14 Imp qt, 1.37 US qt)
CAUTION:
• Do not mix more than one type of ethylene glycol antifreeze containing corrosion inhibitors for aluminum engine.
• Do not use water containing impurities or oil.
INSP
ADJ
LOW
FULL
COOLANT
Handling notes of coolant:
The coolant is harmful so it should be handled with special care.
WARNING
• When coolant splashes to your eye.
Thoroughly wash your eye with water
and see your doctor.
• When coolant splashes to your clothes.
Quickly wash it away with water and
then with soap.
• When coolant is swallowed.
Quickly make him vomit and take him
to a doctor.
10. Install:
• Radiator cap
11. Fill:
• Coolant reservoir tank
Midway a between maximum and minimum marks on the tank.
a
3 - 7
Page 73
RADIATOR CAP INSPECTION/
RADIATOR CAP OPENING PRESSURE INSPECTION
12. Install:
• Coolant reservoir cap
13. Start the engine and let it warm up for several minutes.
14. Turn off the engine and inspect the coolant
level.
Refer to “COOLANT LEVEL INSPECTION”
section.
OTE:
Before checking the coolant level wait a few
minutes until the coolant settles.
Impossible to maintain the specified pressure for 10 seconds → Replace.
COOLING SYSTEM INSPECTION
1. Inspect:
• Coolant level
2. Attach:
• Radiator cap tester 1 and adapter 2
Radiator cap tester:
YU-24460-01/90890-01325
Radiator cap tester adapter:
YU-33984/90890-01352
3. Apply the specified pressure.
Standard pressure:
180 kPa (1.8 kg/cm
2
, 15.6 psi)
2
, 25.6 psi)
OTE:
• Do not apply pressure more than specified
pressure.
• Radiator should be filled fully.
4. Inspect:
• Pressure
Impossible to maintain the specified pressure for 10 seconds → Repair.
• Radiator 1
• Radiator hose joint 2
Coolant leakage → Repair or replace.
• Radiator hose 3
Swelling → Replace.
CLUTCH ADJUSTMENT
1. Check:
• Clutch lever free play a
Out of specification → Adjust.
Clutch lever free play a:
8 ~ 13 mm (0.31 ~ 0.51 in)
3 - 9
Page 75
THROTTLE CABLE ADJUSTMENT
2. Adjust:
• Clutch lever free play
Clutch lever free play adjustment steps:
• Loosen the locknuts 1.
• Adjust the free play by changing their tight-
ening position.
• Tighten the locknuts.
OTE:
• Make minute adjustment on the lever side
using the adjuster 2.
• After adjustment, check proper operation of
clutch lever.
INSP
ADJ
2
1
THROTTLE CABLE ADJUSTMENT
1. Check:
• Throttle grip free play a
Out of specification → Adjust.
Throttle grip free play a:
3 ~ 5 mm (0.12 ~ 0.20 in)
2. Adjust:
• Throttle grip free play
Throttle grip free play adjustment steps:
• Slide the adjuster cover.
• Loosen the locknut 1.
• Turn the adjuster 2 until the specified free
play is obtained.
• Tighten the locknut.
OTE:
Before adjusting the throttle cable free play,
the engine idle speed should be adjusted.
3 - 10
WARNING
After adjusting the throttle cable free
play, start the engine and turn the handlebar to right and left and make sure
that the engine idling does not run faster.
Page 76
THROTTLE LUBRICATION/
HOT STARTER LEVER ADJUSTMENT
THROTTLE LUBRICATION
1. Remove:
• Cover (throttle cable cap) 1
• Cover (grip cap) 2
• Throttle grip cap 3
2. Apply:
• Lithium soap base grease
On the throttle cable end a.
3. Install:
• Throttle grip cap
• Screw (throttle grip cap)
T
4 Nm (0.4 m · kg, 2.9 ft · lb)
.
R
.
• Cover (grip cap)
• Cover (throttle cable cap)
INSP
ADJ
HOT STARTER LEVER ADJUSTMENT
1. Check:
• Hot starter lever free play a
Out of specification → Adjust.
Hot starter lever free play a:
3 ~ 6 mm (0.12 ~ 0.24 in)
2. Adjust:
• Hot starter lever free play
Hot starter lever free play adjustment
steps:
• Loosen the locknut 1.
• Turn the adjuster 2 until free play a is
within the specified limits.
• Tighten the locknut.
OTE:
After adjustment, check proper operation of
hot starter.
3 - 11
Page 77
AIR FILTER CLEANING
AIR FILTER CLEANING
OTE:
Proper air filter maintenance is the biggest key
to preventing premature engine wear and
damage.
CAUTION:
Never run the engine without the air filter
element in place; this would allow dirt and
dust to enter the engine and cause rapid
wear and possible engine damage.
1. Remove:
• Air filter case cover 1
OTE:
Loosen the quick screw 2 and draw the air filter case cover to remove it because its claws
a are inserted in the side cover as shown.
INSP
ADJ
2. Unhook:
• Binder 1
3. Remove:
• Air filter element 1
• Filter guide 2
4. Clean:
• Air filter element
Clean them with solvent.
OTE:
After cleaning, remove the remaining solvent
by squeezing the element.
3 - 12
Page 78
AIR FILTER CLEANING
CAUTION:
• Do not twist the element when squeezing
the element.
• Leaving too much of solvent in the ele-
ment may result in poor starting.
5. Inspect:
• Air filter element
Damage → Replace.
6. Apply:
• Foam-air-filter oil or equivalent oil to the
element
OTE:
• Squeeze out the excess oil. Element should
be wet but not dripping.
• Wipe off the oil left on the element surface
using a clean dry cloth. (Excess oil in the element may adversely affect engine starting.)
INSP
ADJ
7. Install:
• Filter guide 1
OTE:
• Align the projection a on filter guide with the
hole b in air filter element.
• Apply the lithium soap base grease on the
matching surface c on air filter element.
8. Install:
• Air filter element 1
OTE:
Align the projection a on filter guide with the
hole b in air filter case.
9. Hook:
• Binder 1
OTE:
Hook the binder 1 so that it contacts the filter
guide projections a.
3 - 13
Page 79
1
ENGINE OIL LEVEL INSPECTION
ENGINE OIL LEVEL INSPECTION
1. Start the engine, warm it up for several
minutes, and then turn off the engine and
wait for five minutes.
2. Place the machine on a level place and
hold it up on upright position by placing the
suitable stand under the engine.
3. Remove:
• Oil tank cap 1
INSP
ADJ
a
b
4. Inspect:
• Oil level
Oil level should be between maximum a
and minimum b marks.
Oil level is low → Add oil to proper level.
OTE:
When inspecting the oil level, do not screw the
oil tank cap into the oil tank. Insert the gauge
lightly.
(For USA and CDN)
Recommended oil:
At 5 °C (40 °F) or higher È
Yamalube 4 (20W-40) or SAE
20W-40 type SG motor oil
(Non-Friction modified)
At 15 °C (60 °F) or lower É
Yamalube 4 (10W-30) or SAE
10W-30 type SG motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
CAUTION:
• Do not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
• Do not allow foreign material to enter the
crankcase.
3 - 14
Page 80
ENGINE OIL REPLACEMENT
INSP
ADJ
-20-4-10140301050206830864050
10W-30
10W-40
15W-40
20W-40
20W-50
104
122
a
b
˚CTemp.
(Except for USA and CDN)
Recommended oil:
Refer to the following chart for
selection of oils which are
suited to the atmospheric
temperatures.
Recommended engine oil classification:
API STANDARD:
˚F
API “SG” or higher grade
(Designed primarily for
motorcycles)
CAUTION:
• Do not add any chemical additives or use
oils with a grade of CD a or higher.
• Do not use oils labeled “ENERGY CONSERVING II” b or higher. Engine oil also
lubricates the clutch and additives could
cause clutch slippage.
• Do not allow foreign materials to enter the
crankcase.
5. Install:
• Oil tank cap
6. Start the engine and let it warm up for sev-
eral minutes.
7. Turn off the engine and inspect the oil level
once again.
OTE:
Wait a few minutes until the oil settles before
inspecting the oil level.
ENGINE OIL REPLACEMENT
1. Start the engine and warm it up for several
minutes, and then turn off the engine and
wait for five minute.
2. Place the machine on a level place and
hold it on upright position by placing the
suitable stand under the engine.
3. Place a suitable container under the
engine.
3 - 15
Page 81
1
ENGINE OIL REPLACEMENT
4. Remove:
• Oil tank cap 1
• Oil filler cap 2
• Frame oil drain bolt 3
• Crankcase oil drain bolt 4
• Oil filter element drain bolt 5
Drain the crankcase and oil tank (frame)
of its oil.
INSP
ADJ
5. Remove:
• Lower engine bracket
• Oil hose clamp 1
• Bolt (oil hose) 2
• Oil hose 3
• Oil strainer (frame) 4
6. Inspect:
• Oil strainer (frame)
Clogged → Blow.
7. If the oil filter is to be replaced during this
oil change, remove the following parts and
reinstall them.
Replacement steps:
• Remove the oil filter element cover 1 and
oil filter element 2.
• Check the O-rings 3, if cracked or dam-
aged, replace them with a new one.
• Install the oil filter element and oil filter element cover.
Oil filter element cover:
T
.
10 Nm (1.0 m • kg, 7.2 ft • lb)
R
.
3 - 16
Page 82
ENGINE OIL REPLACEMENT
8. Install:
• Copper washer 1
• Oil strainer (frame) 2
T
70 Nm (7.0 m · kg, 50 ft · lb)
.
R
.
• Oil hose 3
• Bolt (oil hose) 4
T
10 Nm (1.0 m · kg, 7.2 ft · lb)
.
R
.
• Oil hose clamp 5
T
2 Nm (0.2 m · kg, 1.4 ft · lb)
.
R
.
• Lower engine bracket
T
10 Nm (1.0 m · kg, 7.2 ft · lb)
.
R
.
9. Install:
• Copper washer
• Oil filter element drain bolt
• Crankcase oil drain bolt
• Frame oil drain bolt
10. Fill:
• Engine oil
New
T
10 Nm (1.0 m · kg, 7.2 ft · lb)
.
R
.
T
20 Nm (2.0 m · kg, 14 ft · lb)
.
R
.
T
23 Nm (2.3 m · kg, 17 ft · lb)
.
R
.
INSP
ADJ
New
Oil quantity:
Total amount:
Periodic oil change:
With oil filter replacement:
11. Check:
• Oil leakage
12. Install:
• Oil tank cap
13. Check:
• Engine oil level
1.4 L (1.23 Imp qt, 1.48 US qt)
1.2 L (1.06 Imp qt, 1.27 US qt)
1.3 L (1.14 Imp qt, 1.37 US qt)
3 - 17
Page 83
OIL PRESSURE INSPECTION/
PILOT SCREW ADJUSTMENT
OIL PRESSURE INSPECTION
1. Check:
• Oil pressure
Checking steps:
• Slightly loosen the oil pressure check bolt
1.
• Start the engine and keep it idling until oil
starts to seep from the oil pressure check
bolt. If no oil comes out after one minute,
turn the engine off so it will not seize.
• Check oil passages and oil pump for damage or leakage.
• Start the engine after solving the problem(s) and recheck the oil pressure.
• Tighten the oil pressure check bolt.
Oil pressure check bolt:
T
.
10 Nm (1.0 m • kg, 7.2 ft • lb)
R
.
INSP
ADJ
PILOT SCREW ADJUSTMENT
1. Adjust:
• Pilot screw 1
Adjustment steps:
OTE:
To optimize the fuel flow at a smaller throttle
opening, each machine’s pilot screw has
been individually set at the factory. Before
adjusting the pilot screw, turn it in fully and
count the number of turns. Record this number as the factory-set number of turns out.
• Turn in the pilot screw until it is lightly
seated.
• Turn out the pilot screw by the factory-set
number of turns.
Pilot screw:
2 turns out (example)
* 1-7/8 turns out
* Except for USA
3 - 18
Page 84
ENGINE IDLING SPEED ADJUSTMENT/
VALVE CLEARANCE INSPECTION AND ADJUSTMENT
ENGINE IDLING SPEED ADJUSTMENT
1. Start the engine and thoroughly warm it up.
2. Attach:
• Inductive tachometer
To spark plug lead.
3. Adjust:
• Engine idling speed
Adjustment steps:
• Adjust the pilot screw.
Refer to “PILOT SCREW ADJUSTMENT”
section.
• Turn the throttle stop screw 1 until the
engine runs at the lowest possible speed.
To increase idle speed → Turn the throt-
tle stop screw 1 in a.
To decrease idle speed → Turn the throt-
tle stop screw 1 out b.
INSP
ADJ
Inductive tachometer:
YU-8036-B
Engine tachometer:
90890-03113
Engine idling speed:
1,900 ~ 2,100 r/min
VALVE CLEARANCE INSPECTION AND
ADJUSTMENT
OTE:
• The valve clearance should be adjusted
when the engine is cool to the touch.
• The piston must be at Top Dead Center
(T.D.C.) on compression stroke to check or
adjust the valve clearance.
1. Remove:
• Seat
• Fuel tank
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
2. Drain:
• Coolant
Refer to “COOLANT REPLACEMENT”
section.
3 - 19
Page 85
VALVE CLEARANCE INSPECTION AND ADJUSTMENT
3. Remove:
• Right radiator
Refer to “RADIATOR” section in the
CHAPTER 4.
• Carburetor
Refer to “CARBURETOR” section in the
CHAPTER 4.
• Spark plug
• Upper engine bracket
• Cylinder head cover
Refer to “CAMSHAFTS” section in the
CHAPTER 4.
4. Remove:
• Timing mark accessing screw 1
• Crankshaft end accessing screw 2
• O-ring
5. Check:
• Valve clearance
Out of specification → Adjust.
INSP
ADJ
Valve clearance (cold):
Intake valve:
0.10 ~ 0.15 mm
(0.0039 ~ 0.0059 in)
Exhaust valve:
0.17 ~ 0.22 mm
(0.0067 ~ 0.0087 in)
Checking steps:
• Turn the crankshaft counterclockwise with
a wrench.
• Align the T.D.C. mark a on the rotor with
the align mark b on the crankcase cover
when piston is at T.D.C. on compression
stroke.
OTE:
In order to be sure that the piston is at Top
Dead Center, the punch mark c on the
exhaust camshaft and the punch mark d on
the intake camshaft must align with the cylinder head surface, as shown in the illustration.
3 - 20
Page 86
VALVE CLEARANCE INSPECTION AND ADJUSTMENT
• Measure the valve clearance e using a
feeler gauge 1.
OTE:
Record the measured reading if the clearance is incorrect.
INSP
ADJ
6. Adjust:
• Valve clearance
Adjustment steps:
• Remove the camshaft (intake and exhaust).
Refer to “CAMSHAFTS” section in the
CHAPTER 4.
• Remove the valve lifters 1 and the pads
2.
OTE:
• Place a rag in the timing chain space to
prevent pads from falling into the crankcase.
• Identity each valve lifter and pad position
very carefully so that they can be reinstalled in their original place.
• Select the proper pad using the pad selecting table.
Pad range
No. 120
~
No. 240
1.20 mm
~
2.40 mm
Pad Availability:
25 increments
Pads are available in
0.05 mm increments
3 - 21
Page 87
VALVE CLEARANCE INSPECTION AND ADJUSTMENT
OTE:
The thickness a of each pad is indicated in
hundreths of millimeters on the pad upper
surface.
• Round off the last digit of the installed pad
number to the nearest increment.
Last digit of pad
number
0, 1 or 20
4, 5 or 65
8 or 910
EXAMPLE:
Installed pad number = 148
Rounded off value = 150
OTE:
Pads can only be selected in 0.05 mm increments.
INSP
ADJ
Rounded value
• Locate the rounded-off value and the measured valve clearance in the chart “PAD
SELECTION TABLE”. The field where
these two coordinates intersect shows the
new pad number to use.
OTE:
Use the new pad number only as a guide
when verifying the valve clearance adjustment.
• Install the new pads 3 and the valve lifters
4.
OTE:
• Apply the engine oil on the valve lifters.
• Apply the molybdenum disulfide oil on the
valve stem ends.
• Valve lifter must turn smoothly when
rotated with a finger.
• Be careful to reinstall valve lifters and pads
in their original place.
• Install the camshafts (exhaust and intake).
Refer to “CAMSHAFTS” section in the
CHAPTER 4.
Pad number: (example)
Pad No. 175 = 1.75 mm
Pad No. 185 = 1.85 mm
3 - 23
Page 89
SPARK ARRESTER CLEANING (For USA)
SPARK ARRESTER CLEANING (For USA)
WARNING
• Be sure the exhaust pipe and muffler are
cool before cleaning the spark arrester.
• Do not start the engine when cleaning the
exhaust system.
INSP
ADJ
1
1
1
1. Remove:
• Bolt (spark arrester) 1
2. Remove:
• Spark arrester 1
Pull the spark arrester out of the muffler.
3. Clean:
• Spark arrester
Tap the spark arrester lightly, then use a
wire brush to remove any carbon deposits.
4. Install:
• Spark arrester
Insert the spark arrester into the muffler
and align the bolt holes.
• Bolt (spark arrester)
T
10 Nm (1.0 m · kg, 7.2 ft · lb)
.
R
.
3 - 24
Page 90
È
CHASSIS/BRAKE SYSTEM AIR BLEEDING
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
WARNING
Bleed the brake system if:
• The system has been disassembled.
• A brake hose has been loosened or
removed.
• The brake fluid is very low.
• The brake operation is faulty.
A dangerous loss of braking performance
may occur if the brake system is not properly bled.
1. Remove:
• Brake master cylinder cap
• Diaphragm
• Protector (rear brake)
2. Bleed:
• Brake fluid
Front
È
Rear
É
INSP
ADJ
É
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful not to
spill any fluid or allow the reservoir to
overflow.
c. Connect the clear plastic tube 2 tightly to
the caliper bleed screw 1.
d. Place the other end of the tube into a con-
tainer.
e. Slowly apply the brake lever or pedal sev-
eral times.
f. Pull the lever in or push down on the
pedal. Hold the lever or pedal in position.
g. Loosen the bleed screw and allow the
lever or pedal to travel towards its limit.
h. Tighten the bleed screw when the lever or
pedal limit has been reached; then
release the lever or pedal.
Bleed screw:
T
.
6 Nm (0.6 m • kg, 4.3 ft • lb)
R
.
3 - 25
i. Repeat steps (e) to (h) until of the air bub-
bles have been removed from the system.
Page 91
FRONT BRAKE ADJUSTMENT
OTE:
If bleeding is difficult, it may be necessary to
let the brake fluid system stabilize for a few
hours. Repeat the bleeding procedure when
the tiny bubbles in the system have disappeared.
j. Add brake fluid to the level line on the res-
ervoir.
WARNING
Check the operation of the brake after
bleeding the brake system.
3. Install:
• Protector (rear brake)
• Diaphragm
• Brake master cylinder cap
INSP
ADJ
EC362040
FRONT BRAKE ADJUSTMENT
1. Check:
• Brake lever position a
Brake lever position a:
Standard positionExtent of adjustment
95 mm (3.74 in)
76 ~ 97 mm
(2.99 ~ 3.82 in)
2. Remove:
• Brake lever cover
3. Adjust:
• Brake lever position
Brake lever position adjustment steps:
• Loosen the locknut 1.
• Turn the adjusting bolt 2 until the lever
position a is within specified position.
• Tighten the locknut.
3 - 26
Locknut:
T
.
5 Nm (0.5 m • kg, 3.6 ft • lb)
R
.
CAUTION:
Be sure to tighten the locknut, as it will
cause poor brake performance.
4. Install:
• Brake lever cover
Page 92
REAR BRAKE ADJUSTMENT/
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
EC364002
REAR BRAKE ADJUSTMENT
1. Check:
• Brake pedal height a
Out of specification → Adjust.
Brake pedal height a:
5 mm (0.20 in)
2. Adjust:
• Brake pedal height
Pedal height adjustment steps:
• Loosen the locknut 1.
• Turn the adjusting nut 2 until the pedal
height a is within specified height.
• Tighten the locknut.
INSP
ADJ
È
É
WARNING
• Adjust the pedal height between the
maximum È and the minimum É as
shown. (In this adjustment, the bolt
end b should protrude out of the
threaded portion 4 but not be less than
2 mm (0.08 in) c away from the brake
pedal 5).
• After the pedal height adjustment, make
sure that the rear brake does not drag.
FRONT BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
• Brake pad thickness a
Out of specification → Replace as a set.
Brake pad thickness:
4.4 mm (0.17 in)
<Limit>: 1.0 mm (0.04 in)
3
3 - 27
2. Replace:
• Brake pad
Brake pad replacement steps:
• Remove the pad pin plug 1.
Page 93
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
• Loosen the pad pin 2.
• Remove the brake hose holder 3 and
brake caliper 4 from the front fork.
• Remove the pad pin and brake pads 5.
• Connect the transparent hose 6 to the
bleed screw 7 and place the suitable container under its end.
• Loosen the bleed screw and push the
brake caliper piston in.
CAUTION:
Do not reuse the drained brake fluid.
• Tighten the bleed screw.
Bleed screw:
T
.
6 Nm (0.6 m • kg, 4.3 ft • lb)
R
.
• Install the brake pads 8 and pad pin.
INSP
ADJ
OTE:
• Install the brake pads with their projections
a into the brake caliper recesses b.
• Temporarily tighten the pad pin at this
point.
• Install the brake hose holder 9 and brake
caliper 0 and tighten the pad pin A.
OTE:
Fit the brake hose holder cut c over the
projection d on the front fork and clamp the
brake hose.
• Brake pedal operation
A softy or spongy feeling → Bleed brake
system.
Refer to “BRAKE SYSTEM AIR BLEEDING” section.
EC36b000
REAR BRAKE PAD INSULATOR
INSPECTION
1. Remove:
• Brake pad
Refer to “REAR BRAKE PAD INSPECTION AND REPLACEMENT” section.
2. Inspect:
• Rear brake pad insulator 1
Damage → Replace.
INSP
ADJ
ÈÉ
BRAKE FLUID LEVEL INSPECTION
1. Place the brake master cylinder so that its
top is in a horizontal position.
2. Inspect:
• Brake fluid level
Fluid at lower level → Fill up.
Lower level
a
Front
È
Rear
É
Recommended brake fluid:
DOT #4
WARNING
• Use only designated quality brake fluid to
avoid poor brake performance.
• Refill with same type and brand of brake
fluid; mixing fluids could result in poor
brake performance.
• Be sure that water or other contaminants
do not enter master cylinder when refilling.
• Clean up spilled fluid immediately to
avoid erosion of painted surfaces or plastic parts.
3 - 31
Page 97
SPROCKETS INSPECTION/DRIVE CHAIN INSPECTION
SPROCKETS INSPECTION
1. Inspect:
• Sprocket teeth a
Excessive wear → Replace.
OTE:
Replace the drive sprocket, rear wheel
sprocket and drive chain as a set.
DRIVE CHAIN INSPECTION
1. Remove:
• Drive chain 1
OTE:
Remove the drive chain using a drive chain
cutter 2.
2. Clean:
• Drive chain
Brush off as much dirt as possible. Then
clean the drive chain using the chain
cleaner.
1
CAUTION:
This machine has a drive chain with small
rubber O-rings 1 between the side plates.
Steam cleaning, high-pressure washes,
certain solvent and kerosene can damage
these O-rings.
INSP
ADJ
3 - 32
3. Inspect:
• O-ring 1 (drive chain)
Damage → Replace the drive chain.
• Roller 2
• Side plate 3
Damage/wear → Replace the drive
chain.
4. Measure:
• Drive chain length (10 links) a
Out of specification → Replace.
Drive chain length (10 links):
<Limit>: 150.1 mm (5.91 in)
Page 98
DRIVE CHAIN INSPECTION
5. Check:
• Drive chain stiffness a
Clean and oil the drive chain and hold as
illustrated.
Stiff → Replace the drive chain.
6. Install:
• Chain joint 1
• O-ring 2
• Drive chain 3
OTE:
When installing the drive chain, apply the lithium soap base grease on the chain joint and
O-rings.
New
INSP
ADJ
7. Install:
• Link plate 4
OTE:
• Press the link plate onto the chain joint using
a drive chain riveter 5.
• Rivet the end of the chain joint using a drive
chain riveter.
• After riveting the chain joint, make sure its
movement is smooth.
8. Lubricate:
• Drive chain
Drive chain lubricant:
SAE 10W-30 motor oil or
suitable chain lubricants
New
3 - 33
Page 99
DRIVE CHAIN SLACK ADJUSTMENT
DRIVE CHAIN SLACK ADJUSTMENT
1. Elevate the rear wheel by placing the suitable stand under the engine.
2. Check:
• Drive chain slack a
Above the seal guard installation bolt.
Out of specification → Adjust.
Drive chain slack:
40 ~ 50 mm (1.6 ~ 2.0 in)
OTE:
Before checking and/or adjusting, rotate the
rear wheel through several revolutions and
check the slack several times to find the tightest point. Check and/or adjust the drive chain
slack with the rear wheel in this “tight chain”
position.
INSP
ADJ
3. Adjust:
• Drive chain slack
Drive chain slack adjustment steps:
• Loosen the axle nut 1 and locknuts 2.
• Adjust the drive chain slack by turning the
adjusters 3.
To tighten → Turn the adjuster 3 coun-
terclockwise.
To loosen → Turn the adjuster 3 clock-
wise and push wheel forward.
• Turn each adjuster exactly the same
amount to maintain correct axle alignment.
(There are marks a on each side of the
drive chain puller alignment.)
OTE:
Turn the adjuster so that the drive chain is in
line with the sprocket, as viewed from the
rear.
3 - 34
CAUTION:
Too small drive chain slack will overload
the engine and other vital parts; keep the
slack within the specified limits.
Page 100
FRONT FORK INSPECTION/
FRONT FORK OIL SEAL AND DUST SEAL CLEANING
• Tighten the axle nut while pushing down
the drive chain.
Axle nut:
T
.
125 Nm (12.5 m • kg, 90 ft • lb)
R
.
• Tighten the locknuts.
Locknut:
T
.
16 Nm (1.6 m • kg, 11 ft • lb)
R
.
INSP
ADJ
EC36C000
FRONT FORK INSPECTION
1. Inspect:
• Front fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage → Repair or
replace.
EC36D001
FRONT FORK OIL SEAL AND DUST SEAL
CLEANING
1. Remove:
• Protector
• Dust seal 1
OTE:
Use a thin screw driver, and be careful not to
damage the inner fork tube and dust seal.
2. Clean:
• Dust seal a
• Oil seal b
OTE:
• Clean the dust seal and oil seal after every
run.
• Apply the lithium soap base grease on the
inner tube.
3 - 35
Loading...
+ hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.