engine YAMAHA GRIZZLY 450 2009 Owner's Guide

7-13
7 With the engine idling, shift the drive select lever
into the low-range position or the high-range posi-
tion. Apply the throttle slowly and smoothly. The
centrifugal clutch will engage and you will start to
accelerate. If the throttle is applied too abruptly, the
front wheels may lift off the ground, resulting in a
loss of directional control. Avoid higher speeds un-
til you are thoroughly familiar 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.
NOTICEECB00250Do not shift from drive position low-range to
high-range or vice versa without coming to a
complete stop. Damage to the engine or drivetrain may occur.
TURNING YOUR ATV
To achieve maximum traction on unpaved surfac-
es in 2WD or 4WD, the two rear wheels turn to-
gether at the same speed. Furthermore, when
riding in 4WD-LOCK (“DIFF. LOCK”), the frontwheels also turn together at the same speed.
Therefore, unless the wheel on the inside of the
turn is allowed 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.
WARNING
EWB01770Always follow proper procedures for turning
as described in this Owner’s Manual. Practice
turning at low speeds before attempting to turn
at faster speeds. Do not turn at speeds too fast
for your skills or the conditions. Operate at a
slow speed and allow extra time and distance
for maneuvers when in 4WD-LOCK (“DIFF.LOCK”).
As you approach a curve, slow down and begin to
turn the handlebars in the desired direction. As you
do so, put your weight on the footboard to the out-
side of the turn (opposite your desired direction)
and lean your upper body into the turn. Use the
throttle to maintain an even speed through the turn.
This maneuver will let the wheel on the inside of
the turn slip slightly, allowing the ATV to make the
turn properly.
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7-17
7 could come off the ground. The ATV could easily
tip over backwards. Apply both the front and rear
brakes gradually, or dismount the ATV immediate-
ly on the uphill side.
WARNING
EWB01781Use the proper gear and maintain a steady
speed when climbing a hill.
If you lose all forward speed:
Keep weight uphill.
Apply the brakes.
Shift into the park position after you are
stopped.
If you begin rolling backwards:
Keep weight uphill.
2WD: Never apply the rear brake while rolling
backwards. Apply the front brake. When fully
stopped, shift into the park position.
4WD or 4WD-LOCK: Apply both front and
rear brakes gradually. When fully stopped,
shift into the park position.
Dismount on uphill side or to a side if pointed
straight uphill. Turn the ATV around and re-
mount, following the procedure described inthe Owner’s Manual.RIDING 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, select the low-range position
and change to 4WD or 4WD-LOCK 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.U37S60E0.book Page 17 Thursday, June 5, 2008 6:51 PM

8-1
8
EBU28782
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 TIP
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
9*Drive shaft univer-
sal jointLubricate with lithium-soap-based grease.√√√
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*Stabilizer bushesCheck for cracks or other damage, and replace if
necessary.√√√
13*Rear knuckle pivotsLubricate with lithium-soap-based grease.√√√
14*Steering shaftLubricate with lithium-soap-based grease.√√√
15*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
16*Engine mountCheck for cracks or other damage, and replace if
necessary.√√√
17*Axle bootsCheck for cracks or other damage, and replace if
necessary.√√√√√
18 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√
19Engine oil filter car-
tridgeReplace.√√√
20*Engine oil strainerClean.√√√
21 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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8-14
8 To install the panel
Place the panel in the original position and install
the bolts.
Panel F
To remove the panelPull outward on the areas shown.
To install the panelPlace the panel in its original position.
EBU23221Checking 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 panel A. (See page 8-9.)
2. Remove the spark plug cap.
1. Panel FU37S60E0.book Page 14 Thursday, June 5, 2008 6:51 PM

8-15
83. 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).
TIPIf 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.
1. Spark plug cap
1. Spark plug wrench
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8-17
8
TIPIf a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque assoon as possible.
4. Install the spark plug cap.
5. Install the panel.EBU23326Engine oil and oil filter cartridge The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Remove panel F. (See page 8-9.)
3. Check the engine oil level on a cold engine.
TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-tles for an accurate reading.
4. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag.
5. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.1. Engine oil filler cap
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8-18
8
TIPThe engine oil should be between the minimumand maximum level marks.
6. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
7. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
8. Install the panel.To change the engine oil (with or without oil fil-
ter cartridge replacement)
1. Place the ATV on a level surface.
2. Remove panel F. (See page 8-9.)
3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Place an oil pan under the engine to collect
the used oil.
5. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.1. Dipstick
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt
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8-19
8
TIPSkip steps 6–10 if the oil filter cartridge is not beingreplaced.
6. Remove panels D and E. (See page 8-9.)
7. Remove the oil filter cartridge with an oil filter
wrench.
TIPAn oil filter wrench is available at a nearby Yamahadealer.
8. Apply a thin coat of engine oil to the O-ring of
the new oil filter cartridge.
1. Oil filter cartridge
1. Oil filter wrench
U37S60E0.book Page 19 Thursday, June 5, 2008 6:51 PM