2008 YAMAHA WOLVERINE 450 warning

4-6
4
WARNING
EWB00161Always stop the ATV before changing from
two-wheel drive to four-wheel drive and vice-
versa. The ATV handles differently in two-
wheel drive than in four-wheel drive in some
circumstances. Changing from two-wheel
drive to four-wheel drive or vice-versa while
moving may cause the ATV to unexpectedly
handle differently. This could distract the oper-
ator and increase the risk of losing control andof causing an accident.
EBU18280Throttle lever Once the engine is running, movement of the throt-
tle lever will increase the engine speed.
Regulate the speed of the ATV by varying the
throttle position. Because the throttle is spring-
loaded, the ATV will decelerate, and the engine will
return to an idle any time the hand is removed from
the throttle lever.
Before starting the engine, check the throttle to be
sure it is operating smoothly. Make sure it returns
to the idle position as soon as the lever is released.
1. On-Command four-wheel-drive switch “2WD”/“4WD”
1. Throttle lever
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4-7
4
WARNING
EWB00250Malfunction of the throttle could make it diffi-
cult to speed up or slow down when you need
to. This could cause an accident. Check the op-
eration of the throttle lever before you start the
engine. If the throttle does not work smoothly,
check for the cause. Correct the problem be-fore riding the ATV or consult a Yamaha dealer.EBU18321Speed limiter Your ATV was delivered with an adjustable speed
limiter. The speed limiter keeps the throttle from
fully opening, even when the throttle lever is
pushed to the maximum.
1. Loosen the locknut.
2. To increase the maximum engine power avail-
able and the maximum speed of the ATV, turn
the adjusting screw in direction (a). To de-
crease the maximum engine power available
and the maximum speed of the ATV, turn the
adjusting screw in direction (b).3. Tighten the locknut.
WARNING
EWB00240Improper adjustment of the speed limiter and
throttle could cause throttle cable damage or
improper throttle operation. You could lose
control, have an accident or be injured. Do not
turn the adjusting screw out more than 12 mm
(0.47 in) or the throttle cable could be dam-
aged. Always make sure the throttle lever free
play is adjusted to 3.0–5.0 mm (0.12–0.20 in).(See page 8-37.)1. Locknut
2. Adjusting screw
3. No more than 12 mm (0.47 in)
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4-10
4
NOTE:If knocking or pinging occurs, use a different brandof gasoline or higher octane grade.
CAUTION:ECB00070Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and pistonrings, as well as to the exhaust system.
WARNING
EWB00310
Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine or the sun.
Be careful not to spill fuel, especially on the
engine or exhaust pipe which can cause a
fire and severe injury. Wipe up any spilled
fuel immediately.
Do not refuel right after the engine has been
running and is still very hot.
Be sure the fuel tank cap is closed securely.EBU18820Fuel cock The fuel cock supplies fuel from the tank to the car-
buretor while also filtering it.
The fuel cock lever positions are explained as fol-
lows and shown in the illustrations.
1. Fuel level
2. Fuel tank filler tubeRecommended fuel:
Regular unleaded gasoline only with a re-
search octane number of 91 or higher
Fuel tank capacity:
14.5 L (3.83 US gal) (3.19 Imp.gal)
Fuel reserve amount:
4.5 L (1.19 US gal) (0.99 Imp.gal)
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4-16
4
WARNING
EWB00400Always adjust the shock absorber assemblies
on the left and right side to the same setting.
Uneven adjustment can cause poor handling
and loss of stability, which could lead to an ac-cident.EBU19020Adjusting the rear shock absorber as-
sembly The spring preload can be adjusted to suit the rid-
er’s weight and the riding conditions.
Adjust the spring preload as follows.
Turn the adjusting ring in direction (a) to increase
the spring preload and thereby harden the suspen-
sion, and in direction (b) to decrease the spring
preload and thereby soften the suspension.
NOTE:A special wrench can be obtained at a Yamahadealer to make this adjustment.1. Spring preload adjusting ring
2. Position indicator
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5-1
5
EBU19200
PRE-OPERATION CHECKS
EBU19222Pre-operation check list Before operating this ATV, be sure to check the items listed in the following table.
WARNING
EWB00480Always inspect your ATV each time you use it to make sure it is in safe operating condition.
Always follow the inspection and maintenance procedures and schedules described in the Owner’sManual. Failure to inspect increases the possibility of an accident or equipment damage.NOTE:The maintenance of some items in the table has to be performed by a Yamaha dealer. Refer to the periodicmaintenance charts on page 8-3 to determine which service should be performed by a Yamaha dealer.
ITEM ROUTINE PAGE
FuelCheck fuel level in fuel tank, and add recommended fuel if neces-
sary.
Check fuel line for leakage. Correct if necessary.4-9, 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, 8-22
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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5-3
5
EBU19540Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-9.)
WARNING
EWB00520
Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine or the sun.
Be careful not to spill fuel, especially on the
engine or exhaust pipe which can cause a
fire and severe injury. Wipe up any spilled
fuel immediately.
Do not refuel right after the engine has been
running and is still very hot.
Be sure the fuel tank cap is closed securely.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 8-22.)
EBU19600Differential gear oil Make sure that the differential gear oil is at the
specified level. Add oil as necessary. (See page
8-24.)EBU19630Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-26.)NOTE:The coolant level must be checked on a cold en-
gine since the level varies with engine tempera-ture.
WARNING
EWB00510Wait for the engine and radiator to cool before
removing the radiator cap. You could be
burned by hot fluid and steam blown out under
pressure. Always put a thick rag over the cap
when opening. Allow any remaining pressureto escape before completely removing the cap.
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5-4
5
EBU19731Front 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 le-
ver. If the free play is incorrect, adjust it. (See
page 8-42.)
Check for correct brake pedal height. If the pedal
height is incorrect, have a Yamaha dealer adjust
it.
Check the operation of the brake levers and
pedal. They should move smoothly and there
should be a firm feeling when the brakes are ap-
plied. If not, have a Yamaha dealer check the
brake system.
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-39.)Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or brake fluid reservoirs. Apply the
brakes firmly for one minute. If a lever moves slow-
ly 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 for wear. (See page 8-38.)
WARNING
EWB00580Always check the brakes at the start of every
ride. Do not ride the ATV if you find any prob-
lem with the brakes or you could lose braking
ability, which could lead to an accident. If a
problem cannot be corrected by the adjust-
ment procedures provided in this manual, havea Yamaha dealer check for the cause.
Recommended brake fluid:
DOT 4
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5-5
5
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.EBU19811Tires
WARNING
EWB00591Use of improper tires on this ATV, or operation
of this ATV with improper or uneven tire pres-
sure, may cause loss of control, increasing
your risk of accident.
Pay attention to the following.
The tires listed below have been approved
by Yamaha Motor Manufacturing Corpora-
tion of America for this model. Other tire
combinations are not recommended.
Front:
Manufacturer/model:
MAXXIS/M937
Size:
AT23 x 8R12
Type:
TubelessRear:
Manufacturer/model:
MAXXIS/M938
Size:
AT23 x 10R12
Type:
Tubeless

The tires should be set to the recommended
pressure:
Recommended tire pressure:
Front:
40.0 kPa (5.8 psi) (0.400 kgf/cm²)
Rear:
40.0 kPa (5.8 psi) (0.400 kgf/cm²)
Check and adjust tire pressures when the
tires are cold.
Tire pressures must be equal on both
sides.
Tire pressure below the minimum speci-
fied could cause the tire to dislodge from
the rim under severe riding conditions.
Minimum tire pressure:
Front:
37.0 kPa (5.3 psi) (0.370 kgf/cm²)
Rear:
37.0 kPa (5.3 psi) (0.370 kgf/cm²)
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