maintenance YAMAHA YFZ450R 2011 Owner's Manual

8-26
87. Start the engine and rev it up approximately
twenty times while momentarily creating ex-
haust system back pressure by blocking the
end of the muffler with a shop towel.
8. Stop the engine and allow the exhaust pipe to
cool.
9. Check the gasket for damage, and replace it if
necessary.
10. Install the gasket and the purging bolt, and
then tighten the bolt to the specified torque.
WARNING
EWB02380Never run the engine in an enclosed area when
purging the spark arrester, otherwise it could
cause injury to the eyes, burns, carbon monox-
ide poisoning, possibly leading to death, and
start a fire.
Always let the exhaust system cool prior to
touching exhaust components.
Always wear eye protection, and make sure
no one is behind the ATV.
Make sure there are no combustible materi-
als in the area.EBU29701Adjusting the throttle lever free play The throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
1. Purging bolt
2. Gasket
2
1
Tightening torque:
Purging bolt:
27 Nm (2.7 m·kgf, 20 ft·lbf)
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8-27
8 The throttle lever free play should measure 2.0–
4.0 mm (0.08–0.16 in) at the throttle lever. Period-
ically check the throttle lever free play and, if nec-
essary, adjust it as follows.
1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.5. Slide the rubber cover to its original position.
EBU24060Valve clearance The valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.EBU24130Checking the front and rear brake pads The front and rear brake pads must be checked for
wear at the intervals specified in the periodic main-
tenance and lubrication chart.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
3 2
4 (a)(b)
1
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8-30
8

Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.
Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.
Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.
As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.EBU24291Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,
have the oil seals of the master cylinders and cali-
pers as well as the brake hoses replaced at the in-
tervals listed below or whenever they are damaged
or leaking.
Oil seals: Replace every two years.
Brake hoses: Replace every four years.
EBU24394Checking the front brake lever free play The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever should have no
free play as shown. If there is free play, have a
Yamaha dealer check the brake system.EBU24613Checking the brake pedal height The brake pedal height must be checked and, if
necessary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.1. No brake lever free play
1
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8-31
8 The top of the brake pedal should be positioned
11.7 mm (0.46 in) below the top of the footrest as
shown. If the brake pedal is not positioned as spec-
ified, have a Yamaha dealer adjust it.
EBU24712Adjusting the parking brake free play The parking brake free play must be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
Cable length “A” should measure 47–51 mm
(1.85–2.01 in). Adjust the parking brake free play
as follows.1. Release the parking brake by moving the
parking brake lever to the right.
2. Fully loosen the locknut and the adjusting bolt
at the rear brake caliper.
3. Slide the rubber cover back.
4. Loosen the locknut on the brake cable.
5. Turn the adjusting nut on the brake cable in di-
rection (a) to increase the cable length, and in
direction (b) to decrease it.1. Brake pedal height
1
1. Adjusting bolt
2. Cable length “A”
3. Locknut
1
2
3
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8-33
8 The brake light switch for the brake pedal can be
adjusted as follows, but the front brake light switch
should be adjusted by a Yamaha dealer.
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).
EBU30151Adjusting 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. To increase the clutch lever free play, turn the
adjusting nut at the clutch lever in direction (a),
and to decrease it, turn the nut in direction (b).
If the specified free play cannot be obtained,
proceed with the following steps.
2. Fully turn the adjusting nut at the clutch lever
in direction (a) to loosen the clutch cable.
3. Slide the rubber cover back.
4. Loosen the clutch cable locknut, located to-
wards the center of the cable.1. Rear brake light switch
2. Rear brake light switch adjusting nut
1
2(a)(b)
1. Clutch lever free play
2. Clutch lever free play adjusting nut (clutch lever)
1
(a)
(b)
2
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8-36
8vent this from occurring, keep the drive
chain slack within the specified limits.
[ECB00542]
6. Pull the rod out, and then tighten the rear axle
pinch bolts to the specified torque in the order
shown.
EBU24882Lubricating 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.NOTICEECB00561The drive chain must be lubricated after wash-
ing the ATV or riding in the rain or wet areas.1. Clean the drive chain with kerosene and a
small soft brush. NOTICE: To prevent dam-
aging the O-rings, do not clean the drive
chain with steam cleaners, high-pressure
washers or inappropriate solvents.
[ECB00571]
Tightening torque:
Rear axle pinch bolt:
21 Nm (2.1 m·kgf, 15 ft·lbf)
3124
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8-39
8
EBU24963Checking 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.
EBU24995Lubricating the swingarm pivots The swingarm pivots must be lubricated by a
Yamaha dealer at the intervals specified in the pe-
riodic maintenance and lubrication chart. Recommended lubricant:
Lithium-soap-based greaseRecommended lubricant:
Lithium-soap-based grease
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8-41
8 Right side
EBU25092Lubricating the steering shaft The steering shaft must be lubricated by a Yamaha
dealer at the intervals specified in the periodic
maintenance and lubrication chart.TIPFor parts equipped with a grease nipple, use a
grease gun.
EBU29186Battery The battery is located under the seat. (See page
4-10.)
This model is equipped with a VRLA (Valve Regu-
lated Lead Acid) battery. There is no need to check
the electrolyte or to add distilled water. However,
the battery lead connections need to be checked
and, if necessary, tightened.NOTICEECB00620Never attempt to remove the battery cell seals,
as this would permanently damage the battery.
WARNING
EWB02160Battery 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.
1. Upper grease nipple
2. Lower grease nippleRecommended lubricant:
Lithium-soap-based grease
1
2
2
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Maintenance and lubrication chart ................................. 8-5
Maintenance chart, emission control system ................. 8-3
Model label ................................................................... 11-2NNeutral indicator light ..................................................... 4-2OOwner’s manual and tool kit ........................................... 8-2PParking ........................................................................... 6-4
Parking brake free play, adjusting ................................ 8-31
Parking brake lever ........................................................ 4-7
Parking on a slope ......................................................... 6-5
Part locations ................................................................. 3-1RRiding your ATV ............................................................. 7-1SSafety information .......................................................... 2-1
Seat .............................................................................. 4-10
Shifting ........................................................................... 6-2
Shift pedal ...................................................................... 4-8
Shift pedal, checking .................................................... 8-38
Shock absorber assemblies, adjusting the front .......... 4-11
Shock absorber assembly, adjusting the rear .............. 4-16
Spark arrester, cleaning ............................................... 8-24
Spark plug, checking .................................................... 8-12
Specifications ............................................................... 10-1
Speed limiter .................................................................. 4-5
Start switch ..................................................................... 4-4
Steering shaft, lubricating ............................................. 8-41
Storage ........................................................................... 9-2
Suspension, lubricating the upper and lower arm
pivots .......................................................................... 8-40Swingarm pivots, lubricating ........................................ 8-39
TTail/brake light .............................................................. 8-47
Throttle lever ........................................................... 4-4, 5-5
Throttle lever free play, adjusting ................................. 8-26
Tires ............................................................................... 5-5
Troubleshooting ........................................................... 8-49
Troubleshooting charts ................................................. 8-50VValve clearance ............................................................ 8-27
Vehicle identification number ....................................... 11-1WWheel hub bearings, checking ..................................... 8-39
Wheel, installing ........................................................... 8-48
Wheel, removing .......................................................... 8-47
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