2008 YAMAHA YFZ450 Owners Manual

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parking brake lever to the right.
2. Fully loosen the locknut and the adjusting bolt
at the rear brake caliper.
3. Loosen the locknut on the brake cable.
4. Turn the adjusting nut on the brake cable in di-
rection (a) to increase the cable length, and in
direction (b) to decrease it.
NOTE:

If the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.
5. Tighten the locknut on the brake cable.6. Turn in the adjusting bolt at the rear brake cal-
iper until it feels tight, then turn it out 1/8 turn
and tighten its locknut to the specified torque.CAUTION:
ECB00520
When tightening the locknut, hold the adjust-
ing bolt with a wrench so that it does not turn
together with the locknut.WARNING
EWB02090
Operating with improperly serviced or adjust-
ed brakes could cause the brakes to malfunc-
tion, resulting in reduced braking
performance. This could increase the chance
of a collision or accident. After adjusting the
parking brake free play, block the rear of the
ATV off the ground and spin the rear wheels.
Check to make sure there is no brake drag. If
brake drag is noticed, perform the adjustment
again.
1. Locknut
2. Adjusting nut
(a)
(b)
12

Tightening torque:
Locknut (rear brake caliper):
16 Nm (1.6 m·kgf, 12 ft·lbf)

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EBU24740
Brake light switches
The operation of the brake light switches must be
checked and, if necessary, adjusted at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
The brake light switch for the brake pedal can be
adjusted as follows, but the other brake light
switches should be adjusted by a Yamaha dealer.
NOTE:

The brake light switch is properly adjusted when
the brake light comes on just before braking takes
effect.
Turn the adjusting nut while holding the brake light
switch in place. To make the brake light come on
earlier, turn the adjusting nut in direction (a). To
make the brake light come on later, turn the adjust-
ing nut in direction (b).
EBU24820
Adjusting the clutch lever free play
The clutch lever free play must be checked and, if
necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The clutch lever free play should measure 8.0–
13.0 mm (0.31–0.51 in) as shown. If the free play
is incorrect, adjust it as follows.
1. Brake light switch
2. Brake light switch adjusting nut
(a)
(b)1
2

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1. Loosen the locknut at the clutch lever.
2. To increase the clutch lever free play, turn the
adjusting bolt at the clutch lever in direction
(a), and to decrease it, turn the bolt in direction
(b).
3. Tighten the locknut at the clutch lever.
If the specified free play cannot be obtained,
proceed with the following steps.
4. Loosen the locknut at the clutch lever.
5. Fully turn the adjusting bolt at the clutch lever
in direction (a) to loosen the clutch cable.
6. Loosen the locknut at the crankcase.7. To increase the clutch lever free play, turn the
adjusting nut at the crankcase in direction (a),
and to decrease it, turn the nut in direction (b).
8. Tighten the locknut at the crankcase and the
clutch lever.NOTE:
If the specified free play cannot be obtained as de-
scribed above or if the clutch does not operate cor-
rectly, have a Yamaha dealer check the internal
clutch mechanism.
1. Clutch lever free play
2. Clutch lever free play adjusting bolt
1
(a)
(b)
2

1. Locknut
2. Clutch lever free play adjusting nut (crankcase)
(a)
(b)
2
1

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EBU24880
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:

ECB00560
The drive chain must be lubricated after wash-
ing the ATV or riding in the rain.
1. Clean the drive chain with kerosene and asmall soft brush.
CAUTION:

ECB00570
To prevent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-pres-
sure washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant.
CAUTION:

ECB00580
Do not use engine oil or any other lubricants
for the drive chain, as they may contain sub-
stances that could damage the O-rings.
EBU24900
Checking and lubricating the cables
The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
1. O-rings
1

Recommended lubricant:
Engine oil

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WARNING

EWB02130
Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could re-
strict the operation of controls and lead to an
accident or injury.
EBU24921
Checking and lubricating the brake and
clutch levers
The operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Brake lever
Clutch lever
Recommended lubricants:
Brake lever:
Silicone grease
Clutch lever:
Lithium-soap-based grease (all-purpose
grease)

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EBU24931
Checking and lubricating the brake and
shift pedals
The operation of the brake and shift pedals should
be checked before each ride, and the pedal pivots
should be lubricated if necessary.
Brake pedal
EBU24962
Checking the wheel hub bearings
The front and rear wheel hub bearings must be
checked at the intervals specified in the periodic
maintenance and lubrication chart. If there is play
in a wheel hub or if a wheel does not turn smoothly,
have a Yamaha dealer check the wheel hub bear-
ings.
EBU24992
Lubricating the swingarm pivots
The swingarm pivots must be lubricated at the in-
tervals specified in the periodic maintenance and
lubrication chart. Recommended lubricants:
Brake pedal:
Silicone grease
Shift pedal:
Lithium-soap-based grease (all-purpose
grease)
Recommended lubricant:
Lithium-soap-based grease

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EBU25030
Lubricating the upper and lower arm
pivots
The upper and lower arm pivots must be lubricated
at the intervals specified in the periodic mainte-
nance and lubrication chart.
Lubricate the pivoting points using a grease gun.
Left side
Recommended lubricant:
Lithium-soap-based grease
1. Upper grease nipple
2. Lower grease nipple
21

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Right side

EBU25222
Battery
This model is equipped with a sealed-type (MF)
battery, which does not require any maintenance.
There is no need to check the electrolyte or to add
distilled water. Check and, if necessary, tighten the
battery lead connections.
CAUTION:

ECB00620
Never attempt to remove the battery cell seals,
as this would permanently damage the battery.WARNING
EWB02160
Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can
cause severe burns. Avoid contact with skin,
eyes or clothing. Always shield your eyes
when working near batteries.
Antidote:
EXTERNAL: Flush with water.
INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of ig-
nition away. Ventilate when charging or using
in an enclosed space.
KEEP OUT OF REACH OF CHILDREN.
To charge the battery
Have a Yamaha dealer charge the battery as soon
as possible if it seems to have discharged. Keep in
mind that the battery tends to discharge more
quickly if the ATV is equipped with optional electri-
cal accessories.
1. Upper grease nipple
2. Lower grease nipple
2 1