Yamaha YFM25BX User Manual

READ THIS MANUAL CAREFULLY!

It contains important safety information.

OWNER’S MANUAL

YFM25BX

WARNING

This ATV should not be ridden by anyone under 16 years of age.

1P0-F8199-13LIT-11626-21-16

EBU17091

EBU17170

INTRODUCTION

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Congratulations on your purchase of the Yamaha YFM25BX. This ATV represents the result of many years
of Yamaha experience in the production of fine sporting, touring, and pace-setting racing machines. With
the purchase of this Yamaha, you can now appreciate the high degree of craftsmanship and reliability that
have made Yamaha a leader in these fields.
This manual will provide you with a good basic understanding of the features and operation of this ATV.

This manual includes important safety information. It provides information about special tech­niques and skills necessary to ride the ATV. It also includes basic maintenance and inspection proce-

dures. If you have any questions regarding the operation or maintenance of your ATV, please consult a
Yamaha dealer.

AN IMPORTANT SAFETY MESSAGE:

● READ THIS MANUAL TOGETHER WITH TIPS FOR THE ATV RIDER CAREFULLY AND COMPLETE-

LY BEFORE OPERATING YOUR ATV. MAKE SURE YOU UNDERSTAND ALL INSTRUCTIONS.

● PAY CLOSE ATTENTION TO THE WARNING AND CAUTION LABELS ON THE ATV.

● NEVER OPERATE AN ATV WITHOUT PROPER TRAINING OR INSTRUCTION. FREE TRAINING IS

AVAILABLE TO ANYONE WHO BUYS A NEW ATV. CALL 1-800-887-2887 FOR MORE INFORMA­TION.

● THIS ATV, AND ANY OTHER ATV OVER 90 cc, SHOULD NOT BE RIDDEN BY ANYONE UNDER 16

YEARS OF AGE.

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IMPORTANT MANUAL INFORMATION

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FAILURE TO FOLLOW THE WARNINGS CONTAINED IN THIS MANUAL CAN RESULT IN SERIOUS IN­JURY OR DEATH.
Particularly important information is distinguished in this manual by the following notations:

The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED!

Failure to follow WARNING instructions could result in severe injury

WARNING

or death to the ATV operator, a bystander, or a person inspecting or
repairing the ATV.

CAUTION:

NOTE:

A CAUTION indicates special precautions that must be taken to avoid
damage to the ATV.

A NOTE provides key information to make procedures easier or clearer.

* Product and specifications are subject to change without notice.

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IMPORTANT NOTICE

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Welcome to the Yamaha world of motor sports!
This ATV is designed and manufactured for OFF-ROAD use only. It is illegal and unsafe to operate this ATV
on any public street, road or highway.
This ATV complies with all applicable OFF-ROAD noise level and spark arrester laws and regulations in
effect at the time of manufacture.
Please check your local riding laws and regulations before operating this ATV.

EBU17401

YFM25BX

OWNER’S MANUAL

©2007 by Yamaha Motor Corporation, U.S.A.

1st edition, April 2007

AFFIX DEALER

LABEL HERE

Any reprinting or unauthorized use

without the written permission of

Yamaha Motor Corporation, U.S.A.

All rights reserved.

is expressly prohibited.

Printed in U.S.A.

P/N LIT-11626-21-16

EWB00010

WARNING

Indicates a potential hazard that could result
in serious injury or death.

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TABLE OF CONTENTS

SAFETY INFORMATION .............................. 1-1

LOCATION OF THE WARNING AND

SPECIFICATION LABELS ............................ 2-1

DESCRIPTION .............................................. 3-1

Left view ...................................................... 3-1

Right view.................................................... 3-1

Controls and instruments ............................ 3-2

INSTRUMENT AND CONTROL

FUNCTIONS .................................................. 4-1

Main switch ................................................ 4-1

Indicator lights ............................................ 4-2

Handlebar switches .................................... 4-2

Throttle lever .............................................. 4-3

Speed limiter .............................................. 4-4

Front brake lever .........................................4-5

Brake pedal and rear brake lever ...............4-5

Parking brake ..............................................4-6

Shift pedal ...................................................4-7

Drive select lever ........................................4-7

Recoil starter ...............................................4-8

Fuel tank cap ..............................................4-9

Fuel .............................................................4-9

Fuel cock ..................................................4-10

Starter (choke) ..........................................4-12

Seat ..........................................................4-12

Storage compartment ...............................4-13

Front carrier ..............................................4-14

Rear carrier ...............................................4-14

Adjusting the rear shock absorber

assembly .................................................4-15

PRE-OPERATION CHECKS ..........................5-1

Pre-operation check list ..............................5-1

Fuel .............................................................5-3

Engine oil ....................................................5-3

Final gear oil ...............................................5-3

Front and rear brakes .................................5-3

Throttle lever ...............................................5-4

Tires ............................................................5-5

Measuring the tire pressure ........................5-6

Tire wear limit .............................................5-7

Chassis fasteners ....................................... 5-7

Instruments, lights and switches ................ 5-7

Battery ........................................................ 5-7

SLIDING AND SKIDDING .........................7-31

WHAT TO DO IF........................................7-33

WHAT TO DO............................................7-33

OPERATION .................................................. 6-1

Starting a cold engine ................................ 6-1

Starting a warm engine .............................. 6-3

Operating the drive select lever and

driving in reverse ...................................... 6-3

Shifting ....................................................... 6-5

Engine break-in .......................................... 6-7

Parking ....................................................... 6-7

Parking on a slope ..................................... 6-8

Accessories and loading ............................ 6-9

RIDING YOUR ATV ...................................... 7-1

GETTING TO KNOW YOUR ATV............... 7-2

RIDE WITH CARE AND GOOD

JUDGEMENT............................................ 7-3

BE CAREFUL WHERE YOU RIDE........... 7-13

TURNING YOUR ATV .............................. 7-19

CLIMBING UPHILL ................................... 7-21

RIDING DOWNHILL.................................. 7-25

CROSSING A SLOPE............................... 7-27

CROSSING THROUGH SHALLOW

WATER ................................................... 7-29

RIDING OVER ROUGH TERRAIN ........... 7-31

PERIODIC MAINTENANCE AND MINOR

REPAIR ..........................................................8-1

Owner’s manual and tool kit .......................8-1

Periodic maintenance chart for the

emission control system ...........................8-3

General maintenance and lubrication

chart ..........................................................8-5

Checking the spark plug .............................8-8

Engine oil and oil filter element .................8-10

Final gear oil .............................................8-15

Cleaning the air filter element ...................8-18

Cleaning the spark arrester ......................8-21

Adjusting the carburetor ............................8-22

Adjusting the engine idling speed .............8-23

Adjusting the throttle cable free play .........8-24

Valve clearance ........................................8-24

Adjusting the drive select lever safety

system cable ...........................................8-25

Checking the front brake pads and rear

brake shoes ............................................8-25

Checking the brake fluid level ...................8-26

Changing the brake fluid ...........................8-27

Checking the front brake lever free play ...8-27

Adjusting the brake pedal position, free

play and the rear brake lever free play ... 8-28

Axle boots ................................................ 8-31

Brake light switches ................................. 8-31

Adjusting the clutch free play ................... 8-32

Checking and lubricating the cables ........ 8-33

Checking and lubricating the front and

rear brake levers .................................... 8-34

Checking and lubricating the brake

pedal ...................................................... 8-35

Checking the wheel hub bearings ............ 8-35

Lubricating the swingarm pivots ............... 8-35

Lubricating the steering shaft ................... 8-35

Battery ...................................................... 8-36

Replacing the fuse ................................... 8-39

Replacing a headlight bulb ....................... 8-40

Adjusting a headlight beam ...................... 8-42

Replacing the tail/brake light bulb ............ 8-43

Removing a wheel .................................... 8-44

Installing a wheel ...................................... 8-44

Troubleshooting ....................................... 8-46

Troubleshooting chart .............................. 8-47

CLEANING AND STORAGE.......................... 9-1

Cleaning ..................................................... 9-1

Storage ....................................................... 9-2

SPECIFICATIONS .......................................10-1

CONSUMER INFORMATION.......................11-1

Identification numbers ...............................11-1

Noise regulation ........................................11-3

Maintenance record ..................................11-4

YAMAHA MOTOR CORPORATION,

U.S.A. ATV LIMITED WARRANTY .........11-5

YAMAHA EXTENDED SERVICE

(Y.E.S.) ...................................................11-7

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SAFETY INFORMATION

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AN ATV IS NOT A TOY AND CAN BE HAZARD­OUS TO OPERATE.

An ATV handles differently from other vehicles, in­cluding motorcycles and cars. A collision or roll­over can occur quickly, even during routine
maneuvers such as turning and riding on hills or
over obstacles, if you fail to take proper precau­tions.
SEVERE INJURY OR DEATH can result if you do
not follow these instructions:

● Read this manual and all labels carefully and fol-

low the operating procedures described.

● Never operate an ATV without proper training or

instruction. Take a Training Course.
should receive training from a certified instruc­tor. Contact an authorized ATV dealer or call 1­800-887-2887 to find out about the training
courses nearest you.

● Always follow the age recommendation:

– A child under 16 years old should never oper­ate an ATV with engine size greater than 90 cc.

Beginners

1

● Never allow a child under age 16 to operate an

ATV without adult supervision, and never allow
continued use of an ATV by a child if he or she
does not have the abilities to operate it safely.

● Never carry a passenger on an ATV.

● Always avoid operating an ATV on any paved

surfaces, including sidewalks, driveways, park­ing lots and streets.

● Never operate an ATV on any public street, road

or highway, even a dirt or gravel one.

● Never operate an ATV without wearing an ap-

proved motorcycle helmet that fits properly. You
should also wear eye protection (goggles or face
shield), gloves, boots, a long-sleeved shirt or a
jacket, and long pants.

● Never consume alcohol or drugs before or while

operating this ATV.

● Never operate at speeds too fast for your skills

or the riding conditions. Always go at a speed
that is proper for the terrain, visibility, operating
conditions, and your experience.

● Never attempt wheelies, jumps, or other stunts.

1-1

● Always inspect your ATV each time you use it to

make sure it is in safe operating condition. Al-

1

ways follow the inspection and maintenance
procedures and schedules described in this
manual.

● Always keep both hands on the handlebars and

both feet on the footboards of the ATV during
operation.

● Always go slowly and be extra careful when op-

erating on unfamiliar terrain. Always be alert to
changing terrain conditions when operating the
ATV.

● Never operate on excessively rough, slippery or

loose terrain until you have learned and prac­ticed the skills necessary to control the ATV on
such terrain. Always be especially cautious on
these kinds of terrain.

● Always follow proper procedures for turning as

described in this manual. Practice turning at low
speeds before attempting to turn at faster
speeds and never turn at excessive speeds.

● Never operate the ATV on hills too steep for the

ATV or for your abilities. Practice on smaller hills
before attempting larger hills.

● Always follow proper procedures for climbing

hills as described in this manual. Check the ter­rain carefully before you start up any hill. Never
climb hills with excessively slippery or loose sur­faces. Shift your weight forward. Never open the
throttle suddenly or make sudden gear changes.
Never go over the top of a hill at high speed.

● Always follow proper procedures for going down

hills and for braking on hills as described in this
manual. Check the terrain carefully before you
start down any hill. Shift your weight backward.
Never go down a hill at high speed. Avoid going
down a hill at an angle that would cause the ve­hicle to lean sharply to one side. Go straight
down the hill where possible.

● Always follow proper procedures for crossing

the side of a hill as described in this manual.
Avoid hills with excessively slippery or loose sur­faces. Shift your weight to the uphill side of the
ATV. Never attempt to turn the ATV around on
any hill until you have mastered the turning tech­nique described in this manual on level ground.
Avoid crossing the side of a steep hill if possible.

● Always use proper procedures if you stall or roll

backwards when climbing a hill. To avoid stall­ing, use the proper gear and maintain a steady

1-2

speed when climbing a hill. If you stall or roll
backwards, follow the special procedure for
braking described in this manual. Dismount on
the uphill side or to a side if pointed straight up­hill. Turn the ATV around and remount, following
the procedure described in this manual.

● Always check for obstacles before operating in a

new area.

● Never attempt to operate over large obstacles,

such as large rocks or fallen trees. Always follow
proper procedures when operating over obsta­cles as described in this manual.

● Always be careful when skidding or sliding.

Learn to safely control skidding or sliding by
practicing at low speeds and on level, smooth
terrain. On extremely slippery surfaces, such as
ice, go slowly and be very cautious in order to re­duce the chance of skidding or sliding out of con­trol.

● Never operate an ATV in fast flowing water or in

water deeper than that recommended in this
manual. Remember that wet brakes may have
reduced stopping ability. Test your brakes after
leaving water. If necessary, apply them several
times to let friction dry out the linings.

● Always be sure there are no obstacles or people

behind you when you operate in reverse. When
it is safe to proceed in reverse, go slowly.

● Always use the size and type of tires specified in

this manual.

● Always maintain proper tire pressure as de-

scribed in this manual.

● Never modify an ATV through improper installa-

tion or use of accessories.

● Never exceed the stated load capacity for an

ATV. Cargo should be properly distributed and
securely attached. Reduce speed and follow in­structions in this manual for carrying cargo or
pulling a trailer. Allow greater distance for brak­ing.

FOR MORE INFORMATION ABOUT ATV SAFE­TY, call the Consumer Products Safety Commis-

sion at 1-800-638-2772, or the ATV Distributor’s
Safety Hotline at 1-800-852-5344.

1

1-3

EWB00021

WARNING

1

POTENTIAL HAZARD
Improper handling of gasoline.
WHAT CAN HAPPEN
Gasoline can catch fire and you could be
burned.
HOW TO AVOID THE HAZARD
Always turn off the engine when refueling.
Do not refuel right after the engine has been
running and is still very hot.
Do not spill gasoline on the engine or ex­haust pipe/muffler when refueling.
Never refuel while smoking, or in the vicinity
of sparks, open flames, or other sources of
ignition such as the pilot lights of water
heaters and clothes dryers.
When transporting the ATV in another vehi­cle, be sure it is kept upright and that the
fuel cock is in the “OFF” position. Other­wise, fuel may leak out of the carburetor or
fuel tank.
WHAT CAN HAPPEN
Gasoline is poisonous and can cause inju­ries.

HOW TO AVOID THE HAZARD
If you should swallow some gasoline or in­hale a lot of gasoline vapor, or get some gas­oline in your eyes, seek medical help
immediately. If gasoline spills on your skin,
wash with soap and water. If gasoline spills
on your clothing, change your clothes.

EWB00030

WARNING

POTENTIAL HAZARD
Starting or running the engine in a closed ar­ea.

1-4

WHAT CAN HAPPEN
Exhaust fumes are poisonous and may
cause loss of consciousness and death
within a short time.
HOW TO AVOID THE HAZARD
Always operate your ATV in an area with ad­equate ventilation.

1

1-5

2

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LOCATION OF THE WARNING AND SPECIFICATION LABELS

2-1

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Read and understand all of the labels on your ATV. These labels contain important information for safe and
proper operation.
Never remove any labels from your ATV. If a label becomes difficult to read or comes off, request a replace­ment label from your Yamaha dealer.

2

2-2

2-322-423-1

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DESCRIPTION

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Left view

3

1. Headlights

2. Fuel cock

3. Recoil starter

4. Fuses

5. Battery

6. Tail/brake light

7. Rear shock absorber assembly spring preload adjusting
ring

8. Engine oil drain bolt

9. Shift pedal

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Right view

1. Spark arrester

2. Storage compartment and tool kit

3. Air filter case

4. Engine oil filler cap

5. Front brake fluid reservoir

6. Brake pedal

7. Clutch adjusting screw

8. Oil filter element

9. Rear brake light switch

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Controls and instruments

1. Rear brake lever

2. Handlebar switches

3. Parking brake lock plate

4. Starter (choke)

5. Drive select lever

6. Main switch

7. Fuel tank cap

8. Throttle lever

9. Front brake lever

NOTE:

The ATV you have purchased may differ slightly
from the figures shown in this manual.

3

3-2

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INSTRUMENT AND CONTROL FUNCTIONS

EWB00010

WARNING

Indicates a potential hazard that could result in
serious injury or death.

EBU17760

4

Main switch

The positions of the main switch are as follows:

ON

All electrical systems are supplied with power. The
headlights and taillight come on when the light
switch is on, and the engine can be started. The
key cannot be removed.

OFF

All electrical systems are off. The key can be re­moved.

1. Main switch

4-1

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Indicator lights

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Handlebar switches

4

1. Reverse indicator light “R”

2. Neutral indicator light “N”

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Reverse indicator light “”

This indicator light comes on when the transmis­sion is in the reverse position.

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Neutral indicator light “”

This indicator light comes on when the transmis­sion is in the neutral position.

1. Light switch “ //OFF”

2. Engine stop switch “ / ”

3. Start switch “”

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Engine stop switch “ / ”

Set this switch to “” before starting the engine.
The engine stop switch controls the ignition and
stops the engine when it is running. Use this switch
to stop the engine in an emergency situation. The
engine will not start or run when this switch is set
to “”.

4-2

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Start switch “”

Push this switch to crank the engine with the start­er.

ECB00050

CAUTION:

See the starting instructions on page 6-1 prior
to starting the engine.

4

EBU18151

Light switch “ //OFF”

Set this switch to “” to turn on the low beams
and the taillight. Set the switch to “” to turn on
the high beams and the taillight. Set the switch to
“OFF” to turn off all the lights.

ECB00040

CAUTION:

Do not use the headlights with the engine
turned off for an extended period of time, oth­erwise the battery may discharge to the point
that the starter motor will not operate properly.
If this should happen, remove the battery and
recharge it.

EBU18270

Throttle lever

Once the engine is running, movement of the throt­tle lever will increase the engine speed.
Regulate the speed of the ATV by varying the
throttle position. Because the throttle is spring­loaded, the ATV will decelerate, and the engine will
return to an idle any time the hand is removed from
the throttle lever.

1. Throttle lever

Before starting the engine, check the throttle to be
sure it is operating smoothly. Make sure it returns
to the idle position as soon as the lever is released.

4-3

EWB00200

WARNING

POTENTIAL HAZARD
Malfunction of throttle.
WHAT CAN HAPPEN
The throttle could be hard to operate, mak­ing it difficult to speed up or slow down
when you need to. This could cause an acci­dent.
HOW TO AVOID THE HAZARD
Check the operation of the throttle lever be­fore you start the engine. If it does not work
smoothly, check for the cause. Correct the
problem before riding the ATV. Consult a
Yamaha dealer if you can’t find or solve the
problem yourself.

EBU18311

Speed limiter

Your ATV was delivered with an adjustable speed
limiter. The speed limiter keeps the throttle from
fully opening, even when the throttle lever is
pushed to the maximum.

1. Loosen the locknut.

2. To increase the maximum engine power avail­able and the maximum speed of the ATV, turn
the adjusting screw in direction (a). To de-

crease the maximum engine power available
and the maximum speed of the ATV, turn the
adjusting screw in direction (b).

4

1. Locknut

2. Adjusting screw

3. No more than 12 mm (0.47 in)

3. Tighten the locknut.

4-4

EWB00190

WARNING

POTENTIAL HAZARD
Improper adjustment of the speed limiter
and throttle.
WHAT CAN HAPPEN
The throttle cable could be damaged. Im­proper throttle operation could result. You

4

could lose control, have an accident or be in­jured.
HOW TO AVOID THE HAZARD
Do not turn the adjusting screw out more
than 12 mm (0.47 in). Always make sure the
throttle lever free play is adjusted to 3.0–5.0
mm (0.12–0.20 in). (See page 8-24.)

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Front brake lever

The front brake lever is located on the right handle­bar. To apply the front brake, pull the brake lever
toward the handlebar grip.

1. Front brake lever

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Brake pedal and rear brake lever

The brake pedal is located on the right side of the
ATV and the rear brake lever is located on the left
handlebar. To apply the rear brake, push down on
the brake pedal or pull the brake lever toward the
handlebar grip.

4-5

1. Brake pedal

1. Rear brake lever

EBU18450

Parking brake

Use the parking brake before starting the engine or
parking the ATV, especially on a slope. Apply the
rear brake lever and push down the lock plate to
apply the parking brake. Squeeze the rear brake
lever to release the parking brake.

4

1. Parking brake lock plate

4-6

EWB00170

WARNING

POTENTIAL HAZARD
Improper use of the parking brake.
WHAT CAN HAPPEN
The ATV could start moving unexpectedly if
the parking brake is not applied before start­ing the engine. This could cause loss of con-

4

trol or a collision.
The brake could overheat if you ride the ATV
without releasing the parking brake. You
could lose braking performance which could
cause an accident. You could also wear out
the brakes prematurely.
HOW TO AVOID THE HAZARD
Always set the parking brake before starting
the engine.
Always be sure you have released the park­ing brake before you begin to ride.

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Shift pedal

This ATV is equipped with a constant-mesh 5­speed transmission. The shift pedal is located on
the left side of the engine. Neutral is at the bottom
position.

1. Shift pedal

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Drive select lever

The drive select lever is used for driving the ATV
either forward or in reverse. See the “Operating the
drive select lever and driving in reverse” section on
page 6-3 for the drive select lever operation.

4-7

1. Drive select lever 1. Recoil starter

EBU27371

EWB02361

Recoil starter

Firmly grasp the handle and pull slightly until en­gagement can be felt. Then pull forcefully, being
careful not to pull the rope all the way out.

POTENTIAL HAZARD
Starting the engine in gear or starting the
engine without applying the parking brake.
WHAT CAN HAPPEN
The ATV could start to move unexpectedly,
which could cause an accident.
HOW TO AVOID THE HAZARD
Shift the transmission into the neutral posi­tion and apply the parking brake before
starting the engine.

4-8

4

WARNING

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Fuel tank cap

Remove the fuel tank cap by turning it counter­clockwise.

4

1. Fuel tank cap

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Fuel

Make sure that there is sufficient fuel in the tank.
Fill the fuel tank to the bottom of the filler tube as
shown.

1. Fuel tank filler tube

2. Fuel level

Recommended fuel:

UNLEADED GASOLINE ONLY

Fuel tank capacity:

12.0 L (3.17 US gal) (2.64 Imp.gal)

Fuel reserve amount:

1.6 L (0.42 US gal) (0.35 Imp.gal)

4-9

ECB00070

CAUTION:

Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.

Your Yamaha engine has been designed to use
regular unleaded gasoline with a pump octane
number [(R+M)/2] of 86 or higher, or a research oc­tane number of 91 or higher. If knocking or pinging
occurs, use a different brand of gasoline or premi­um unleaded fuel. Unleaded fuel will give you long­er spark plug life and reduced maintenance cost.

Gasohol

There are two types of gasohol: gasohol contain­ing ethanol and that containing methanol. Gasohol
containing ethanol can be used if the ethanol con­tent does not exceed 10%. Gasohol containing
methanol is not recommended by Yamaha be­cause it can cause damage to the fuel system or
ATV performance problems.

EWB00270

WARNING

POTENTIAL HAZARD
Improper care when refueling.

WHAT CAN HAPPEN
Fuel can spill, which can cause a fire and se­vere injury.
Fuel expands when it heats up. If the fuel
tank is overfilled, fuel could spill out due to
heat from the engine or the sun.
HOW TO AVOID THE HAZARD
Do not overfill the fuel tank. Be careful not to
spill fuel, especially on the engine or ex­haust pipe. Wipe up any spilled fuel immedi­ately. Be sure the fuel tank cap is closed
securely.
Do not refuel right after the engine has been
running and is still very hot.

EBU18820

Fuel cock

The fuel cock supplies fuel from the tank to the car­buretor while also filtering it.
The fuel cock lever positions are explained as fol­lows and shown in the illustrations.

4

4-10

OFF

ON

4

1. Arrow mark positioned over “OFF” 1. Arrow mark positioned over “ON”

With the fuel cock lever in this position, fuel will not
flow. Always turn the fuel cock lever to this position
when the engine is not running.

With the fuel cock lever in this position, fuel flows
to the carburetor. Turn the fuel cock lever to this
position when starting the engine and riding.

4-11