engine YAMAHA GRIZZLY 450 2012 Owner's Guide

7-12
7Select 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, shifting procedures,
and turning techniques in this area before trying
more difficult terrain.
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.
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
until 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.
NOTICEECB00251Do not shift from low-range to high-range or
vice versa without coming to a complete stop.
Damage to the engine or drive train may occur.TURNING YOUR ATV
WARNING
EWB01771Always 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. ATV could go
out of control, causing a collision or overturn.To achieve maximum traction on unpaved surfac-
es, the two rear wheels 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 tech-
nique 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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7-16
7remount, following the procedure described in the
Owner
’s Manual. WARNING! Stalling, rolling
backwards or improperly dismounting while
climbing a hill could result in ATV overturning.
If you cannot control the ATV, dismount imme-
diately on the uphill side.
[EWB01802]
RIDING DOWNHILL
WARNING
EWB01621Going down a hill improperly could cause
overturns or loss of control. Always follow
proper procedures for going down hills as de-
scribed in this Owner ’s Manual.

Always check the terrain carefully before
you start down any hill.
Never operate the ATV on hills too steep for
the ATV or for your abilities. The ATV can
overturn more easily on extremely steep hills
than on level surfaces or small hills.
Shift your weight backward and to the up
side of the hill.
Never go down a hill at high speed.
Avoid going down a hill at an angle that
would cause the ATV to lean sharply to one
side. Go straight down the hill where possi-
ble.
Improper braking can cause the wheels on
the uphill side to come off the ground or
cause loss of traction. Apply brakes gradual-
ly. If in “2WD ”, apply only the rear brake.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 ” before beginning to descend
the hill.
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8-1
8
EBU28783
PERIODIC MAINTENANCE AND ADJUSTMENT
EBU21674Periodic inspection, adjustment, and lubrication
will keep your vehicle in the safest and most effi-
cient condition possible. Safety is an obligation of
the vehicle owner/operator. The most important
points of vehicle inspection, adjustment, and lubri-
cation are explained on the following pages.
WARNING
EWB01841Failure to properly maintain the vehicle or per-
forming maintenance activities incorrectly may
increase your risk of injury or death during ser-
vice or while using the vehicle. If you are not fa-
miliar with vehicle service, have a Yamaha
dealer perform the service.
WARNING
EWB02562Turn off the engine when performing mainte-
nance unless otherwise specified.
A running engine has moving parts that can
catch on body parts or clothing and electri-
cal parts that can cause shocks or fires.

Running the engine while servicing can lead
to eye injury, burns, fire, or carbon monoxide
poisoning - possibly leading to death. See
page 2-3 for more information about carbon
monoxide.
WARNING
EWB02690Brake discs, calipers, drums, and linings can
become very hot during use. To avoid possible
burns, let brake components cool before
touching them.The intervals given in the periodic maintenance
charts should be considered as a general guide
under normal riding conditions. However, DE-
PENDING ON THE WEATHER, TERRAIN, GEO-
GRAPHICAL LOCATION, AND INDIVIDUAL
USE, THE MAINTENANCE INTERVALS MAY
NEED TO BE SHORTENED.
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8-3
8
EBU21743Periodic 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. ITEM CHECK OR MAINTENANCE
JOB INITIAL
EVERY
Whichev- er comes first month136612
km
(mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320
1 *Fuel line 
Check fuel hoses for cracks or other damage, and
replace if necessary. √√√
2 Spark plug 
Check condition and clean, regap, or replace if
necessary. √√√√√
3 *Valves Check valve clearance and adjust if necessary. √ √√√
4 *Carburetor 
Check starter (choke) operation and correct if nec-
essary.
 Check engine idling speed and adjust if neces-
sary. √√√√
5 *Crankcase breather
system 
Check breather hose for cracks or other damage,
and replace if necessary. √√√
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8
13*Rear knuckle pivots Lubricate with lithium-soap-based grease. √√√
14 *Steering shaft Lubricate with lithium-soap-based grease. √√√
15 *Steering system 
Check operation and repair or replace if damaged.
 Check toe-in and adjust if necessary. √√√√√
16 *Engine mount 
Check for cracks or other damage, and replace if
necessary. √√√
17 *Axle boots 
Check for cracks or other damage, and replace if
necessary. √√√√√
18 Engine oil 
Change.
 Check ATV for oil leakage, and correct if neces-
sary. √ √√√
19 Engine oil filter car-
tridge 
Replace. √√√
20 *Engine oil strainer Clean. √√√
21 Differential gear oil 
Change.
 Check ATV for oil leakage, and correct if neces-
sary. √√
22 Final gear oil 
Change.
 Check ATV for oil leakage, and correct if neces-
sary. √ √√√
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev- er comes first month136612
km
(mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320U1CT61E0.book Page 7 Wednesday, April 20, 2011 6:36 PM

8-14
8
To install the panel
Place the panel in the original position and install
the bolts.
Panel E
To remove the panelPull outward on the areas shown.
To install the panelPlace the panel in its original position.
EBU23223Checking 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 8-10.)
2. Remove the spark plug cap.
1. Panel E
1
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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
EBU30240Engine 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 level1. Place the ATV on a level surface.
2. Remove panel E. (See page 8-10.)
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 engine oil 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.
TIPThe engine oil should be between the tip of the dip-
stick and the maximum level mark.1. Engine oil filler cap
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8-18
8
6. If the engine oil is not between the tip of the
dipstick and the maximum level mark, add
sufficient oil of the recommended type to raise
it to the correct level. NOTICE: Be sure the
engine oil is at the correct level, otherwise
engine damage may result.
[ECB00851]
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 E. (See page 8-10.)
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 and its gasket to
drain the oil from the crankcase.1. Engine oil dipstick
2. Maximum level mark
3. Tip of the engine oil dipstick
1. Engine oil drain bolt
2. Gasket
12
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8-19
8
TIPSkip steps 6–10 if the oil filter cartridge is not being
replaced.6. Remove panels C and D. (See page 8-10.)
7. Remove the oil filter cartridge with an oil filter wrench.
TIPAn oil filter wrench is available at a nearby Yamaha
dealer.8. Apply a thin coat of engine oil to the O-ring ofthe new oil filter cartridge.
1. Oil filter cartridge
1. Oil filter wrench
U1CT61E0.book Page 19 Wednesday, April 20, 2011 6:36 PM