2005 YAMAHA YFZ450 service

8-75
EBU13970
Idle speed adjustment
A special tester is needed to check the engine
r/min on this model.
Therefore, take the ATV to a Yamaha dealer to
have the idle speed adjusted.
EBU03030
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. Specified idle speed:
1,750–1,850 r/min
U5TG61.book Page 75 Friday, April 2, 2004 11:28 AM

8-87
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.
U5TG61.book Page 87 Friday, April 2, 2004 11:28 AM

8-89 a. Brake lever free play
a. Jeu du levier de frein
a. Juego de la palanca de freno
EBU11880
Front brake lever free play
The front brake lever should have a free play of
zero mm at the lever end. If not, have a Yamaha
dealer check the brake system.
WARNING
_ Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability
which could lead to an accident.
After servicing:

Make sure the brakes operate smoothly
and that the free play is correct.


Make sure the brakes do not drag.


Make sure the brakes are not spongy. All
air must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
should be performed by a Yamaha dealer.
_
U5TG61.book Page 89 Friday, April 2, 2004 11:28 AM

8-91 a. Brake pedal position
a. Position de la pédale de frein
a. Posición del pedal del freno
EBU10790
Brake pedal height adjustment
The top of the brake pedal should be positioned
11.7 mm below the top of the footrest. If not, have
a Yamaha dealer adjust it.
WARNING
_ Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident. After servic-
ing:

Make sure the brakes operate smoothly
and that the brake pedal position is cor-
rect.


Make sure the brakes do not drag.


Make sure the brakes are not spongy. All
air must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These procedures
should be performed by a Yamaha dealer.
_
U5TG61.book Page 91 Friday, April 2, 2004 11:28 AM

8-107 1. O-rings
1. Joints toriques
1. Juntas tóricas
EBU08050
Lubricating the drive chain
The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows.CAUTION:_ The drive chain must be lubricated after wash-
ing the ATV or riding in the rain. _1. Clean the drive chain with kerosene and a
small soft brush.CAUTION:_ To prevent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-pres-
sure washers or inappropriate solvents. _
U5TG61.book Page 107 Friday, April 2, 2004 11:28 AM

8-136
4. Enfoncer la fixation d’ampoule de phare et la tour-
ner dans le sens inverse des aiguilles d’une montre
pour la retirer.
5. Retirer l’ampoule défectueuse et la remplacer par
une neuve.
AVERTISSEMENT
_ Ne pas toucher l’ampoule de phare tant qu’elle est al-
lumée ou immédiatement après son extinction. Il y a
risque de brûlure et d’incendie si l’ampoule chaude
entre en contact avec un produit inflammable. Atten-
dre que l’ampoule soit refroidie avant de la toucher
ou de la déposer. _ATTENTION:_ Ne jamais toucher le verre d’une ampoule de phare
afin de ne pas laisser de résidus graisseux. La graisse
réduit la transparence du verre mais aussi la lumino-
sité de l’ampoule, ainsi que sa durée de service. Net-
toyer soigneusement toute crasse ou trace de doigts
sur l’ampoule avec un chiffon imbibé d’alcool ou de
diluant pour peinture. _
4. Empuje el portabombillas del faro hacia dentro
y gírelo hacia la izquierda para extraerlo.
5. Extraiga la bombilla defectuosa y reemplácela
por una bombilla nueva.
ADVERTENCIA
_ No toque una bombilla del faro cuando esté ca-
liente ni inmediatamente después de haberla
apagado.Podría sufrirse una quemadura o pro-
vocarse un incendio si la bombilla entrara en
contacto con algo. _AT E N C I O N :_ No toque la parte de vidrio de la bombilla del faro
para no ensuciarla con grasa, porque de lo con-
trario se afectarían adversamente la transparen-
cia del vidrio, la luminosidad de la bombilla, y la
vida de servicio de la bombilla. Limpie bien todas
las huellas dactilares que pudiera haber en la
bombilla empleando un paño humedecido en al-
cohol o disolvente. _
U5TG61.book Page 136 Friday, April 2, 2004 11:28 AM

8-143
EBU04130
Troubleshooting
Although Yamaha machines receive a rigid in-
spection before shipment from the factory, trouble
may occur during operation.
Any problem in the fuel, compression, or ignition
systems can cause poor starting and loss of pow-
er. The troubleshooting chart describes a quick,
easy procedure for making checks. If your ma-
chine requires any repair, take it to a Yamaha
dealer.
The skilled technicians at a Yamaha dealership
have the tools, experience, and know-how to prop-
erly service your machine. Use only genuine
Yamaha parts on your machine. Imitation parts
may look like Yamaha parts, but they are often in-
ferior. Consequently, they have a shorter service
life and can lead to expensive repair bills.
U5TG61.book Page 143 Friday, April 2, 2004 11:28 AM

10-2
10
Engine oil:
Type
Recommended engine oil classification API Service SE, SF, SG type or higher
Quantity:
Without oil filter element replacement
With oil filter element replacement1.75 L
1.85 L MODEL YFZ450
-20˚ -10˚ 0˚
10˚20˚ 30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30
CAUTION:In order to prevent clutch slippage (since the en-
gine oil also lubricates the clutch), do not mix any
chemical additives. Do not use oils with a diesel
specification of “CD” or oils of a higher quality
than specified. In addition, do not use oils labeled
“ENERGY CONSERVING II” or higher.
U5TG61.book Page 2 Friday, April 2, 2004 11:28 AM