Page 7 of 392

FBU00946
INTRODUCTION
Félicitations pour l’achat du YFM400FP/YFM400FW
de Yamaha. Ce modèle représente le fruit de nombreuses
années d’expérience Yamaha dans la production de véhi-
cules de sport, de tourisme et de course. Ce véhicule per-
mettra à son pilote de pleinement apprécier la perfection
technique et la fiabilité qui ont fait de Yamaha un leader
dans ces domaines.
Ce manuel apporte une meilleure compréhension des ca-
ractéristiques et du fonctionnement du véhicule. Le ma-
nuel donne en outre des conseils importants relatifs à
la sécurité. Il informe sur les compétences et techni-
ques particulières indispensables au pilotage du véhi-
cule.
Ce manuel explique également les procédés d’ins-
pection et d’entretien élémentaires. Les concessionnaires
Yamaha sont au service de leur clientèle et répondront à
toute question concernant le fonctionnement ou l’entre-
tien de ce véhicule.
SBU00946
INTRODUCCIÓN
Le felicitamos por su compra de la Yamaha
YFM400FP/YFM400FW. Representa el resultado
de muchos años de experiencia de Yamaha en la
producción de máquinas deportivas, de turismo, y de
competición que marcan el ritmo de las carreras.
Con la compra de esta Yamaha, podrá apreciar el
alto grado de perfección técnica y fiabilidad que han
convertido a Yamaha en el líder de estos campos.
El presente manual le proporcionará un buen cono-
cimiento básico de las características y el manejo del
ATV.
También contiene indicaciones importan-
tes acerca de la seguridad y aporta información
sobre las técnicas y habilidades especiales ne-
cesarias para conducir el ATV, así como los pro-
cedimientos básicos de mantenimiento e inspección.
Si tiene alguna duda respecto al mantenimiento o
manejo del ATV, consulte a su concesionario
Yamaha.
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4-34
FBU00095
Starter (enrichisseur) “”
La mise en marche à froid requiert un mélange air-carbu-
rant plus riche. C’est le starter qui remplit cette fonction
d’enrichissement du mélange.
Déplacer dans la direction a
pour mettre le starter (enri-
chisseur) en service.
Déplacer dans la direction b
pour mettre le starter (enri-
chisseur) hors service.
La marche à suivre correcte est décrite à la section “Mise
en marche d’un moteur froid”. (Pour plus de détails, voir
page 6-4.)
SBU00095
Starter (choke) “”
Cuando el motor está frío, requiere una mezcla más
rica de combustible para arrancar. Esta mezcla se
suministra a través de un circuito separado, el circui-
to del “starter”.
Mueva en la dirección
a para conectar el starter
(choke).
Mueva en la dirección
b para desconectar el starter
(choke).
Consulte el apartado de “Arranque en frío del motor”
para ver la operación adecuada. (Consulte la página
6-4.)
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5-17
EBU11620
Fittings and fasteners
Always check the tightness of chassis fittings and
fasteners before a ride. Take the machine to a
Yamaha dealer or refer to the Service Manual for
correct tightening torque.
EBU01003
Lights
Check the headlights and tail/brake light to make
sure they are in working condition. Repair as nec-
essary for proper operation.
EBU11700
Switches
Check the operation of all switches. Have a
Yamaha dealer repair as necessary for proper op-
eration.
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Page 252 of 392
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 254 of 392

8-3 1. Owner’s manual
2. Low-pressure tire gauge
1. Manuel du propriétaire
2. Manomètre basse pression pour pneus
1. Manual del propietario
2. Manómetro de baja presión
1. Owner’s tool kit
1. Trousse à outils du propriétaire
1. Equipo de herramientas del propietario
EBU00256
Owner’s manual and tool kit
You are recommended to put this owner’s manual
and low-pressure tire gauge in the vinyl bag and
always carry them in the storage box. Put the own-
er’s tool kit in the space under the seat. The ser-
vice 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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Page 259 of 392

8-8 * It is recommended that these items be serviced by a Yamaha dealer.
NOTE:
Recommended brake fluid: DOT 4
Brake fluid replacement:
When disassembling the master cylinder or caliper cylinder, replace the brake fluid. Normally check
the brake fluid level and add fluid as required.
On the inner parts of the master cylinder and caliper cylinder, replace the oil seals every two years.
Replace the brake hoses every four years, or if cracked or damaged.
Drive select lever
safety system*Check operation.
Adjust if necessary.Wheels*Check balance/damage/runout.
Repair if necessary.Wheel bearing*Check bearing assemblies for looseness/damage.
Replace if damaged.Steering system*Check operation.
Replace if damaged.
Check toe-in.
Adjust if necessary.Axle boots*Check condition.
Replace if damaged.Fittings and fasteners*Check all chassis fittings and fasteners.
Correct if necessary.
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
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Page 304 of 392
8-53 1. Locknut 2. Adjusting nut
1. Contre-écrou 2.Écrou de réglage
1. Contratuerca 2. Tuerca de ajuste
EBU00303
Valve clearance adjustment
The correct valve clearance changes with use, re-
sulting in improper fuel/air supply or engine noise.
To prevent this, the valve clearance must be ad-
justed regularly. This adjustment however, should
be left to a professional Yamaha service techni-
cian.
EBU00305
Select lever safety system cable adjustment
The select lever safety system cable stretches
with use, resulting in improper function.
To prevent this, the cable must be adjusted regu-
larly. This adjustment, however, should be left to a
Yamaha dealer.
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8-61
EBU11860
Brake fluid replacement
Complete fluid replacement should be done only
by trained Yamaha service personnel. Have a
Yamaha dealer replace the following components
during periodic maintenance or when they are
damaged or leaking.
Replace the oil seals every two years.
Replace the brake hoses every four years.
U4SH6B.book Page 61 Tuesday, May 27, 2003 4:39 PM