2004 YAMAHA YFM50S maintenance

EBU14290
INTRODUCTION
Congratulations on your purchase of the
Yamaha YFM50. It represents the result of
many years of Yamaha experience in the pro-
duction of fine sporting, touring, and pacesetting
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 machine. This manual includes important
safety information. It provides information
about special techniques and skills neces-
sary to ride your machine. It also includes
basic maintenance and inspection procedures. If
you have any questions regarding the operation
or maintenance of your machine, please consult
a Yamaha dealer.
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OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine ......................6-11
Warming up ........................................6-11
To start out and accelerate .................6-13
To decelerate .....................................6-17
Engine break-in ..................................6-19
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 ...............................7-39
Climbing uphill ....................................7-43
Riding downhill ...................................7-55
Crossing a slope .................................7-59
Crossing through shallow water .........7-63Riding over rough terrain ....................7-67
Sliding and skidding ...........................7-69
What to do if ......................................7-73
What to do .........................................7-73
PERIODIC MAINTENANCE AND
ADJUSTMENT .........................................8-1
Owner’s manual and tool kit .................8-3
Periodic maintenance/lubrication .........8-7
Engine oil ............................................8-13
Final gear oil .......................................8-19
Spark plug inspection .........................8-23
Air filter cleaning .................................8-27
Carburetor adjustment ........................8-35
Idle speed adjustment ........................8-37
Valve clearance adjustment ...............8-39
Cam chain adjustment ........................8-39
Front and rear brake shoe
inspection .........................................8-41
Front brake lever free play
adjustment ........................................8-436
7
8
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2-5
8Never operate at speeds too fast for your
skills or the conditions. Always go at a speed
that is proper for the terrain, visibility and
operating conditions, and your experience.
8Never attempt wheelies, jumps, or other
stunts.
8Always 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.
8Always keep both hands on the handlebars
and both feet on the footrests of the ATV dur-
ing operation.
8Always go slowly and be extra careful when
operating on unfamiliar terrain. Always be
alert to changing terrain conditions when
operating the ATV.
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5-4
w
Always inspect your ATV each time you use it to make sure the ATV is in safe operating condi-
tion.
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 dam-
age.
XG
Toujours effectuer ces contrôles avant chaque départ afin de s’assurer que le VTT peut être utili-
sé en toute sécurité.
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.
XR
Inspeccionar siempre el ATV cada vez que vaya a utilizarse, para asegurarse de que está en
condiciones de funcionar sin peligro.
Seguir siempre los procedimientos y programas de inspección y mantenimiento descritos en
el “Manual del Propietario”. Si no se inspecciona la máquina, aumenta el riesgo de accidente o
avería.
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7-13
Do not operate after consuming alcohol or
drugs.
Operator’s performance capability is reduced by
the influence of alcohol or drugs.
w
Never consume alcohol or drugs before or
while driving this ATV.
Pre-operation checks
Always perform the pre-operation checks listed
on page 5-1 before riding for safety and proper
care of the machine.
w
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 the ATV before operating or failure to
properly maintain the ATV increases the pos-
sibility of an accident or equipment damage.
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8-1
EBU00516
PERIODIC
MAINTENANCE AND
ADJUSTMENT
Periodic inspection, adjustment and lubrication
will keep your machine in the safest and most
efficient condition possible. Safety is an obliga-
tion of the machine owner. The most important
points of machine inspection, adjustment and
lubrication are explained on the following pages.
w
Never service an engine while it is running.
Moving parts can catch clothing or parts of
the body, causing injury. Electrical compo-
nents can cause shocks or can start fires.
Turn off the engine when performing mainte-
nance unless otherwise specified. Have a
Yamaha dealer perform service if you are not
familiar with machine service.
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8-3
EBU01222
Owner’s manual and tool kit
You are recommended to put this owner’s man-
ual and low-pressure tire gauge in the vinyl bag
and always carry them along with the owner’s
tool kit under the seat. The service information
included in this manual is intended to provide
you, the owner, with the necessary information
for completing your own preventive 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
during a service operation requiring one, take
your machine to a Yamaha dealer to check the
torque settings and adjust them as necessary.
q
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e
1. Owner’s manual
2. Low-pressure tire gauge
3. Owner’s tool kit
1. Manuel du propriétaire
2. Manomètre basse pression pour pneus
3. Trousse à outils du propriétaire
1. Manual del propietario
2. Comprobador de presión de los neumáticos
3. Equipo de herramientas del propietario
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8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
INITIAL EVERY
ITEM ROUTINE 1 3 6 6 1
month months months months year
Valves*9Check valve clearance.
9Adjust if necessary.2 222
Cam chain*9Check chain tension.
9Adjust if necessary.2 222
9Check condition.
Spark plug9Adjust gap and clean.22222
9Replace if necessary.
Air filter element9Clean. Every 20–40 hours.
9Replace if necessary. (more often in wet or dusty areas)
Carburetor*9Check idle speed/choke lever operation.
2222
9Adjust if necessary.
Crankcase breather9Check breather hose for cracks or damage.
system*9Replace if necessary.222
9Check for leakage.
Exhaust system*9Tighten if necessary.222
9Replace gasket if necessary.
Fuel line*9Check fuel hose for cracks or damage.
222
9Replace if necessary.
Engine oil9Replace (warm engine before draining).2 222
Final gear oil9Check oil level/oil leakage.
22
9Replace every 12 months.
Brakes*9Check operation.
22222
9Adjust if necessary.
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