Page 6 of 394
EBU00946
1-INTRODUCTION
Congratulations on your purchase of the Yamaha
YFM250B. It represents the result of many years
of Yamaha experience in the production of fine
sporting, touring, and pacesetting racing ma-
chines. 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 un-
derstanding of the features and operation of this
ATV.
This manual includes important safety in-
formation. It provides information about spe-
cial techniques and skills necessary to ride
your ATV. It also includes basic maintenance and
inspection procedures. If you have any questions
regarding the operation or maintenance of your
ATV, please consult a Yamaha dealer.
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Page 17 of 394

OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine ........................6-9
Warming up ..........................................6-9
Drive select lever operation and
reverse driving ..................................6-11
Shifting ................................................6-15
To start out and accelerate .................6-17
To decelerate ......................................6-19
Engine break-in ...................................6-21
Parking ...............................................6-23
Parking on a slope ..............................6-25
Accessories and loading ....................6-27
RIDING YOUR ATV..................................7-1
Getting to know your ATV .....................7-3
Ride with care and good judgement .....7-5
Be careful where you ride ...................7-27
Turning your ATV ................................7-41
Climbing uphill.....................................7-47
Riding downhill ....................................7-57
Crossing a slope .................................7-61
Crossing through shallow water ..........7-65
Riding over rough terrain ....................7-71
Sliding and skidding ............................7-73
What to do if ........................................7-77
What to do...........................................7-77
67
PERIODIC MAINTENANCE AND
ADJUSTMENT ......................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Engine oil and oil filter element........... 8-17
Final gear oil ....................................... 8-31
Spark plug inspection ......................... 8-37
Air filter element cleaning ................... 8-43
Carburetor adjustment ....................... 8-49
Idle speed adjustment ........................ 8-51
Valve clearance adjustment .............. 8-53
Throttle lever adjustment ................... 8-53
Select lever safety system cable
adjustment ........................................ 8-55
Front brake pad check ........................ 8-55
Rear brake shoe inspection ............... 8-57
Brake fluid level check ........................ 8-59
Brake fluid replacement ...................... 8-61
Front brake lever free play.................. 8-63
Adjusting the brake pedal and rear
brake lever........................................ 8-65
Adjusting the rear brake light switch ... 8-73
Clutch adjustment ............................... 8-75
Cable inspection and lubrication......... 8-77
Brake lever and brake pedal
lubrication ........................................ 8-79
Steering shaft lubrication .................... 8-81
8
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Page 50 of 394
2-5
Never consume alcohol or drugs before or
while operating this ATV.
Never operate at speeds too fast for your skills
or the conditions. Always go at a speed that is
proper for the terrain, visibility, operating condi-
tions, and your experience.
Never attempt wheelies, jumps, or other stunts.
Always inspect your ATV each time you use it
to make sure it is in safe operating condition.
Always 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 dur-
ing 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.
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5-4
WARNING
Always inspect your ATV each time you use it to make sure the ATV is in safe operating condition.
Always follow the inspection and maintenance procedures and schedules described in the
Owner’s Manual. Failure to inspect increases the possibility of an accident or equipment damage.
AVERTISSEMENT
_ Toujours effectuer ces contrôles avant chaque départ afin de s’assurer que le VTT peut être utilisé en toute sécu-
rité. Toujours respecter les procédés et intervalles de contrôle et d’entretien repris dans ce manuel. Omettre ces
contrôles accroît les risques d’accident ou d’endommagement du véhicule. _
ADVERTENCIA
_ Inspeccionar siempre el ATV cada vez que vaya a utilizarse, para asegurarse de que está en condicio-
nes de funcionar sin peligro. Seguir siempre los procedimientos y programas de inspección y mante-
nimiento descritos en el Manual del Propietario. Si no se inspecciona la máquina, aumenta el riesgo de
accidente o avería. _U1P060.book Page 4 Monday, August 2, 2004 12:19 PM
Page 254 of 394
8-1
EBU00516
1-PERIODIC MAINTENANCE AND
ADJUSTMENTPeriodic inspection, adjustment and lubrication will
keep your machine in the safest and most efficient
condition possible. Safety is an obligation of the
machine owner. The most important points of ma-
chine inspection, adjustment and lubrication are
explained on the following pages.
WARNING
Never service an engine while it is running.
Moving parts can catch clothing or parts of the
body, causing injury. Electrical components
can cause shocks or can start fires. Turn off
the engine when performing maintenance un-
less otherwise specified. Have a Yamaha deal-
er perform service if you are not familiar with
machine service.
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Page 256 of 394

8-3 1. Owner’s manual 2. Owner’s tool kit
3. Low-pressure tire gauge
1. Manuel du propriétaire 2. Trousse à outils du propriétaire
3. Manomètre basse pression pour pneus
1. Manual del propietario
2. Juego de herramientas del propietario
3. Manómetro de baja presión
EBU14520
Owner’s manual and tool kit
You are recommended to put this owner’s manual
in the vinyl bag and always carry it on the bottom
of the seat as shown. Put the owner’s tool kit and
low-pressure tire gauge under the seat.
The service information included in this manual is
intended to provide you, the owner, with the nec-
essary information for completing your own pre-
ventive maintenance and minor repairs. The tools
provided in the Owner’s tool kit are sufficient for
this purpose, except that a torque wrench is also
necessary to properly tighten nuts and bolts.NOTE:_ If you do not have a torque wrench available dur-
ing a service operation requiring one, take your
machine to a Yamaha dealer to check the torque
settings and adjust them as necessary. _
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8-7
EBU02621
PERIODIC MAINTENANCE/LUBRICATION
NOTE:_
For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance intervals. How-
ever, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance intervals should be
followed.
_
ITEM ROUTINEWhichever
comes firstINITIAL EVERY
month136612
km
(mi)320
(200)1,200
(750)2,400
(1,500)2,400
(1,500)4,800
(3,000)
hours 20 75 150 150 300
Valves*Check valve clearance.
Adjust if necessary.
Spark plugCheck condition.
Adjust gap and clean.
Replace if necessary.Air filter elementClean.
Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*Check starter (choke) operation.
Adjust engine idling speed.Cylinder head breather
system*Check breather hose for cracks or damage.
Replace if necessary.Exhaust system*Check for leakage.
Tighten if necessary.
Replace gasket(s) if necessary.Fuel line*Check fuel hose for cracks or damage.
Replace if necessary.Engine oil
Replace (Warm engine before draining).Engine oil filter element
Clean.U1P060.book Page 7 Monday, August 2, 2004 12:19 PM
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8-17 1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
1. Bouchon de remplissage d’huile de moteur
2. Jauge
3. Repère de niveau maximum
4. Repère de niveau minimum
1. Tapa del filtro de aceite de motor
2. Varilla de nivel de aceite
3. Marca de nivel máximo
4. Marca de nivel mínimo
EBU11005
Engine oil and oil filter element
The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element cleaned at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Warm up the engine for several minutes, and
then turn it off.
3. Wait at least ten minutes until the oil level set-
tles before checking.
4. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag. Insert
the dipstick in the filler hole (without screwing
it in), and then remove it again to check the oil
level.NOTE:_
Be sure to wait at least ten minutes until the
oil level settles before checking.
The oil level should be between the minimum
and maximum level marks.
_
U1P060.book Page 17 Monday, August 2, 2004 12:19 PM