2010 YAMAHA GRIZZLY 450 Owners Manual

4-22
4 Adjust the spring preload as follows.
Turn the spring preload adjusting ring in direction
(a) to increase the spring preload and thereby
harden the suspension, and in direction (b) to de-
crease the spring preload and thereby soften the
suspension.
TIPA special wrench can be obtained at a Yamaha
dealer to make this adjustment.1. Spring preload adjusting ring
2. Position indicator
1. Special wrenchSpring preload setting:
Minimum (soft):
1
Standard:
2
Maximum (hard):
5
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4-23
4
EBU19182Auxiliary DC jack The auxiliary DC jack is located at the front right
side of the ATV. The auxiliary DC jack can be used
for suitable work lights, radios, etc. The auxiliary
DC jack should only be used when the engine is
running and the light switch is set to “OFF”.
1. Set the light switch to “OFF”.
2. Start the engine. (See page 6-1.)
3. Open the auxiliary DC jack cap, and then in-
sert the accessory power plug into the jack.4. When the auxiliary DC jack is not being used,
cover it with the cap.
NOTICEECB00120
Do not use accessories requiring more than
the above maximum capacity. This may
overload the circuit and cause the fuse to
blow.
If accessories are used without the engine
running or with the headlights turned on, the
battery will lose its charge and engine start-
ing may become difficult.
Do not use an automotive cigarette lighter or
other accessories with a plug that gets hot
because the jack can be damaged.
1. Auxiliary DC jack cap
2. Auxiliary DC jack
1
2
Maximum rated capacity for the auxiliary DC
jack:
DC 12 V, 10 A (120 W)
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5-1
5
EBU19201
PRE-OPERATION CHECKS
EBU19224Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00481Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEM ROUTINE PAGE
FuelCheck fuel level in fuel tank, and add recommended fuel if neces-
sary.
Check fuel line for leakage. Correct if necessary.4-14, 5-3
Engine oilCheck oil level in engine, and add recommended oil to specified lev-
el if necessary.
Check ATV for oil leakage. Correct if necessary.5-3, 8-17
Final gear oilCheck ATV for oil leakage. Correct if necessary. 5-3, 8-21
Differential gear oilCheck ATV for oil leakage. Correct if necessary. 5-3, 8-24
CoolantCheck coolant level in reservoir, and add recommended coolant to
specified level if necessary.
Check cooling system for leakage. Correct if necessary.5-3, 8-26
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5-2
5
Front brakeCheck operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
Check brake pads for wear, and replace if necessary.
Check brake fluid level in reservoir, and add recommended brake
fluid to specified level if necessary.
Check hydraulic system for leakage. Correct if necessary.5-3, 8-39, 8-40, 8-41
Rear brakeCheck operation, and correct if necessary.
Lubricate cables if necessary.
Check lever and pedal free play, and adjust if necessary.5-3, 8-39, 8-42
Throttle leverMake sure that operation is smooth. Lubricate cable and lever hous-
ing if necessary.
Check cable free play, and adjust if necessary.5-4, 8-37
Control cablesMake sure that operation is smooth. Lubricate if necessary. 8-47
Wheels and tiresCheck wheel condition, and replace if damaged.
Check tire condition and tread depth. Replace if necessary.
Check air pressure. Correct if necessary.5-4
Brake pedal Make sure that operation is smooth. Lubricate pedal pivoting point if
necessary.8-48
Brake leversMake sure that operation is smooth. Lubricate lever pivoting points if
necessary.8-47
Axle bootsCheck for cracks or damage, and replace if necessary. 8-45
Chassis fastenersMake sure that all nuts, bolts and screws are properly tightened. 5-7
Instruments, lights and
switchesCheck operation, and correct if necessary. 5-7 ITEM ROUTINE PAGEU37S61E0.book Page 2 Tuesday, June 2, 2009 10:33 AM

5-3
5
EBU19541Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-14.)EBU19560Engine oil Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-17.)EBU19590Final gear oil Make sure that the final gear oil is at the specified
level. Add oil as necessary. (See page 8-21.)EBU19600Differential gear oil Make sure that the differential gear oil is at the
specified level. Add oil as necessary. (See page
8-24.)EBU19631Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-26.)
TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.EBU28531Front and rear brakes Brake levers and brake pedal
Check that there is no free play in the front brake
lever. If there is free play, have a Yamaha dealer
check the brake system.
Check for correct free play in the rear brake lever
and brake pedal. If the free play is incorrect, ad-
just it. (See page 8-42.)
Check operation of the levers and pedal. They
should move smoothly and there should be a
firm feeling when the brake is applied. If not,
have a Yamaha dealer check them.
Brake fluid level (front brake)
Check the brake fluid level. Add fluid if necessary.
(See page 8-40.)
Recommended brake fluid:
DOT 4
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5-4
5Brake fluid leakage (front brake)
Check to see if any brake fluid is leaking out of the
hose, joint or brake fluid reservoir of the front
brake. Apply the brake firmly for one minute. If the
lever moves slowly inward, there may be a leak in
the brake system. If there is any leakage, the brake
system should be checked by a Yamaha dealer.
Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance, check
the brake pads and friction plates for wear. (See
page 8-39.)
EBU19761Throttle lever Check the operation of the throttle lever. It must
open smoothly and spring back to the idle position
when released. Have a Yamaha dealer correct if
necessary.EBU19814Tires Check tire pressure regularly to make sure it is at
the recommended specifications. Also check for
wear and damage.Tire pressure
Use the low-pressure tire gauge to check and ad-
just tire pressures when the tires are cold. Tire
pressures must be equal on both sides.
WARNING! Operation of this vehicle with im-
proper tire pressure may cause severe injury
or death from loss of control or rollover. Tire
pressure below the minimum specified could
also cause the tire to dislodge from the rim un-
der severe riding conditions.
[EWB02541]
Set tire
pressures to the following specifications:
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5-5
5
The low-pressure tire gauge is included as stan-
dard equipment. Make two measurements of the
tire pressure and use the second reading. Dust or
dirt in the gauge could cause the first reading to be
incorrect.Tire wear limit
When the tire groove decreases to 3 mm (0.12 in)
due to wear, replace the tire. Recommended tire pressure:
Fron t
25.0 kPa (0.250 kgf/cm², 3.6 psi)
Rear
25.0 kPa (0.250 kgf/cm², 3.6 psi)
Minimum tire pressure:
Fron t
22.0 kPa (0.220 kgf/cm², 3.2 psi)
Rear
22.0 kPa (0.220 kgf/cm², 3.2 psi)
Maximum tire seating pressure:
Fron t
250 kPa (2.5 kgf/cm², 36 psi)
Rear
250 kPa (2.5 kgf/cm², 36 psi)
1. Low-pressure tire gauge
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5-6
5
Tire information
This ATV is equipped with tubeless tires with
valves.
WARNING
EWB02551Use of improper tires on this ATV may cause
loss of control, increasing your risk of an acci-
dent.After extensive tests, only the tires listed below
have been approved for this model by Yamaha
Motor Manufacturing Corporation of America.Aftermarket tires and rims
The tires and rims that came with your ATV were
designed to match the performance capabilities
and to provide the best combination of handling,
braking, and comfort. Other tires, rims, sizes, and
combinations may not be appropriate.1. Tire wear limit
Front:
Manufacturer/model:
YFM450FAZ CHENG SHIN/C-828
YFM45FGHZ MAXXIS/M979
YFM45FGZ MAXXIS/M979
Size:
AT25 x 8-12
Ty p e :
Tu b e l e s s
Rear:
Manufacturer/model:
YFM450FAZ CHENG SHIN/C-828
YFM45FGHZ MAXXIS/M980
YFM45FGZ MAXXIS/M980
Size:
AT25 x 10-12
Ty p e :
Tu b e l e s s
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