2012 YAMAHA GRIZZLY 450 maintenance

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8
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.
EBU24071Adjusting the drive select lever safety
system cable The drive select lever safety system cable stretch-
es with use, which can result in improper function.
Therefore, the safety system cable should be
checked and adjusted by a Yamaha dealer at the
intervals specified in the periodic maintenance and
lubrication 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.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playU1CT61E0.book Page 38 Wednesday, April 20, 2011 6:36 PM

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8
EBU28413Checking the front brake pads and rear
brake friction plates The front brake pads and the rear brake friction
plates must be checked for wear at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPThis ATV is equipped with a wet, multiple-disc type
rear brake, which is located inside of the final gear
case.EBU24171Front brake pads
Check each front brake pad for damage and mea-
sure the lining thickness. If a brake pad is dam-
aged or if the lining thickness is less than 1.0 mm
(0.04 in), have a Yamaha dealer replace the brake
pads as a set.
TIPThe wheels need to be removed to check the
brake pads. (See page 8-59.)EBU30320Rear brake friction plates
The rear brake friction plates must be checked
and, if necessary, replaced by a Yamaha dealer at
the intervals specified in the periodic maintenance
and lubrication chart.1. Lining thickness
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8
EBU29841Checking the brake fluid level Before riding, check that the brake fluid is above
the minimum level mark. Check the brake fluid lev-
el with the top of the reservoir level. Replenish the
brake fluid if necessary.
WARNING
EWB02720Improper maintenance can result in loss of
braking ability. Observe these precautions:

Insufficient brake fluid may allow air to enter
the brake system, reducing braking perfor-
mance.
Clean the filler cap before removing. Use
only DOT 4 brake fluid from a sealed contain-
er.
Use only the specified brake fluid; otherwise,
the rubber seals may deteriorate, causing
leakage.
Refill with the same type of brake fluid. Add-
ing a brake fluid other than DOT 4 may result
in a harmful chemical reaction.
Be careful that water does not enter the
brake fluid reservoir when refilling. Water
will significantly lower the boiling point of
the fluid and may result in vapor lock.NOTICEECB01160Brake fluid may damage painted surfaces or
plastic parts. Always clean up spilled fluid im-
mediately.As the brake pads wear, it is normal for the brake
fluid level to gradually go down. A low brake fluid
level may indicate worn brake pads and/or brake
system leakage; therefore, be sure to check the
1. Minimum level markSpecified brake fluid:DOT 4
1
U1CT61E0.book Page 40 Wednesday, April 20, 2011 6:36 PM

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8brake pads for wear and the brake system for leak-
age. If the brake fluid level goes down suddenly,
have a Yamaha dealer check the cause before fur-
ther riding.
EBU24281Changing 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 brake master cylinder and
calipers as well as the brake hoses replaced at the
intervals listed below or whenever they are dam-
aged 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.
EBU30342Adjusting the rear brake lever and
brake pedal free play, and the brake
pedal height The rear brake lever and brake pedal free play,
and the brake pedal height must be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
Adjusting the brake lever free play
The brake lever free play should measure 10.0 mm
(0.39 in). If the free play is incorrect, adjust it as fol-
lows.1. No brake lever free play
U1CT61E0.book Page 41 Wednesday, April 20, 2011 6:36 PM

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8
2. To increase the brake pedal free play, turn the
brake pedal free play adjusting nut in direction
(a). To decrease the brake pedal free play,
turn the adjusting nut in direction (b).
3. Tighten the locknut.
EBU24230Axle boots The axle boots must be checked for damage at the
intervals specified in the periodic maintenance and
lubrication chart. Check the axle boots for tears or
damage. If any damage is found, have them re-
placed by a Yamaha dealer.1. Locknut
2. Brake pedal free play adjusting nut
21
(a)
(b)
1. Front axle boot (each side)
1. Rear axle boot (each side)
1
1
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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.
EBU24972Lubricating the drive shaft universal
joint The drive shaft universal joint must be lubricated at
the intervals specified in the periodic maintenance
and lubrication chart.TIPFor parts equipped with a grease nipple, use a
grease gun.Recommended lubricant:Lithium-soap-based grease
U1CT61E0.book Page 49 Wednesday, April 20, 2011 6:36 PM

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8
Front
Rear
EBU25022Checking the stabilizer bushes The stabilizer bushes must be checked for cracks
or damage at the intervals specified in the periodic
maintenance and lubrication chart.
Have a Yamaha dealer replace the stabilizer bush-
es if necessary.EBU25052Lubricating the rear knuckle pivots The rear knuckle pivots must be lubricated at the
intervals specified in the periodic maintenance and
lubrication chart.
1. Grease nipple
1. Grease nipple
1
1
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8
TIPFor parts equipped with a grease nipple, use a
grease gun.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.EBU29188Battery The battery is located under the seat. (See page
4-18.)
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.
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.
Recommended lubricant:
Lithium-soap-based grease
1. Grease nipple
Recommended lubricant:Lithium-soap-based grease
U1CT61E0.book Page 51 Wednesday, April 20, 2011 6:36 PM