2008 YAMAHA WOLVERINE 450 engine

7-6
7 in the Owner’s Manual. Failure to inspect the
ATV before operating or failure to properly
maintain the ATV increases the possibility of
an accident or equipment damage.
WARNING
EWB01440Always use the size and type tires specified in
the Owner’s Manual for this ATV on page 5-5.
Always maintain proper tire pressure as de-
scribed in the Owner’s Manual on page 5-6.
Use of improper tires on this ATV, or operation
of this ATV with improper or uneven tire pres-
sure, may cause loss of control, increasingyour risk of an accident.
Do not operate at speeds too fast for your skills
or the conditions.
WARNING
EWB01450Always go at a speed that is proper for the ter-
rain, visibility and operating conditions, and
your experience. Operating this ATV at speeds
too fast for your skills or the conditions in-
creases your chances of losing control of theATV, which can result in an accident.Speed limiter
For riders less experienced with this model, the
throttle lever housing is equipped with a speed lim-
iter. The speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed to
the maximum. Turning in the adjusting screw limits
the maximum engine power available and de-
creases the maximum speed of the ATV. Turning
in the adjusting screw decreases top speed, and
turning it out increases top speed. (See page 4-7.)
1. Adjusting screw
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7-12
7 Select a large, flat, unpaved area to become famil-
iar with your ATV. Make sure that this area is free
of obstacles and other riders. You should practice
control of the throttle, brakes, and turning tech-
niques in this area before trying more difficult ter-
rain. Always avoid riding on paved surfaces: the
ATV is designed for use on unpaved surfaces only,
and handling maneuvers are more difficult to per-
form on pavement.
Shift to the park position and follow the instruction
on page 6-1 to start the engine. Once it has
warmed up you are ready to begin riding your ATV.
Remember that the engine and exhaust pipe will
be hot when riding and afterwards; do not allow
skin or clothing to come in contact with these com-
ponents.With the engine idling, return the starter (choke) to
the closed position, and shift the drive select lever
into the forward position. Apply the throttle slowly
and smoothly. The centrifugal clutch will engage
and you will start to accelerate. If the throttle is ap-
plied too abruptly, the front wheels may lift off the
ground, resulting in a loss of directional control.
Avoid higher speeds until you are thoroughly famil-
iar with the operation of your ATV.
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. Im-
proper use of the brakes can cause the tires to lose
traction, reducing control and increasing the possi-
bility of an accident.
TURNING YOUR ATV
To achieve maximum traction on unpaved surfac-
es, the two rear wheels are mounted solidly on one
axle and turn together at the same speed. There-
fore, unless the wheel on the inside of the turn is al-
lowed to slip or lose some traction, the ATV will
resist turning. A special turning technique must be
used to allow the ATV to make turns quickly and
easily. It is essential that this skill be learned first at
low speed.
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7-17
7RIDING DOWNHILL
When riding your ATV downhill, shift your weight
as far to the rear and uphill side of the ATV as pos-
sible. Move back on the seat and sit with your arms
straight. Engine compression will do most of the
braking for you. For maximum engine compres-
sion braking effect, change to 4WD before begin-
ning to descend the hill. Improper braking may
cause a loss of traction.
Use caution while descending a hill with loose or
slippery surfaces. Braking ability and traction may
be adversely affected by these surfaces. Improper
braking may also cause a loss of traction.When this ATV is in 4WD, all wheels (front and
rear) are interconnected by the drive train. This
means that applying either the front brake or the
rear brake will brake all wheels. When descending
hills, using either brake lever or the brake pedal will
brake the wheels on the downhill side. Avoid sud-
den application of either the front or rear brake be-
cause the wheels on the uphill side could come off
the ground. Apply both the front and rear brakes
gradually.
Whenever possible, ride your ATV straight down-
hill. Avoid sharp angles which could allow the ATV
to tip or roll over. Carefully choose your path and
ride no faster than you will be able to react to ob-
stacles which may appear.
WARNING
EWB01620Always follow proper procedures for going
down hills as described in this Owner’s Manu-
al.
Note: a special technique is required when
braking as you go down a hill.
Always check the terrain carefully before
you start down any hill.
Shift your weight backward.
Never go down a hill at high speed.
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8-1
8
EBU28781
PERIODIC MAINTENANCE AND MINOR REPAIR
EBU21670Safety is an obligation of the owner. Periodic in-
spection, adjustment and lubrication will keep your
ATV in the safest and best operating condition
possible. The most important points of inspection,
adjustment, and lubrication are explained on the
following pages.
The intervals given in the periodic maintenance
and lubrication chart should be considered as a
general guide under normal riding conditions.
However, DEPENDING ON THE WEATHER,
TERRAIN, GEOGRAPHICAL LOCATION, AND
INDIVIDUAL USE, THE MAINTENANCE INTER-
VALS MAY NEED TO BE SHORTENED.
WARNING
EWB01840Never service an engine while it is running.
Moving parts can catch clothing or parts of the
body, causing injury. Electrical components
can cause shocks or start fires. Turn off the en-
gine when performing maintenance unlessotherwise specified. Have a Yamaha dealer
perform the service if you are not familiar with
maintenance work.EBU21730Owner’s manual and tool kit Be sure to put this owner’s manual in the plastic
bag and always carry it on the bottom of the seat
as shown. Put the owner’s tool kit and low-pres-
sure tire gauge under the seat.1. Owner’s manual
2. Owner’s tool kit
3. Low-pressure tire gauge
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8-3
8
EBU21742Periodic maintenance chart for the emission control system NOTE:
For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,data and technical skills.NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
1*Fuel lineCheck fuel hoses for cracks or other damage, and
replace if necessary.√√√
2 Spark plugCheck condition and clean, regap, or replace if
necessary.√√√√√
3*ValvesCheck valve clearance and adjust if necessary.√ √√√
4*CarburetorCheck starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces-
sary.√√√√
5*Crankcase breather
systemCheck breather hose for cracks or other damage,
and replace if necessary.√√√
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8-6
8
8*SwingarmCheck for excessive play, and correct if necessary.√√√
9*V- b e l tCheck for wear, cracks or other damage, and re-
place if necessary.√ √√√
10*Chassis fastenersMake sure that all nuts, bolts, and screws are
properly tightened.√√√√√
11*Shock absorber as-
sembliesCheck operation and correct if necessary.
Check for oil leakage and replace if necessary.√√√
12*Steering shaftLubricate with lithium-soap-based grease.√√√
13*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
14*Engine mountCheck for cracks or other damage, and replace if
necessary.√√√
15*Axle bootsCheck for cracks or other damage, and replace if
necessary.√√√√√
16 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
17Engine oil filter car-
tridgeReplace.√√√
18*Engine oil strainerClean.√√√
19 Differential gear oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
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8-15
8To install the panel
Place the panel in its original position.
EBU23211Checking the spark plug The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
1. Panel D
1. Spark plug cap
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8-16
8 2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
NOTE:If the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-stead, have a Yamaha dealer check the ATV.2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.1. Spark plug wrench
Specified spark plug:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
U3C262E0.book Page 16 Tuesday, June 26, 2007 3:36 PM