YAMAHA GRIZZLY 250 2011 Owners Manual

8-22
8 5. Remove the sponge material from the air filter
element.6. Clean the sponge material with water or sol-
vent. WARNING! When using solvent to
clean the sponge material, always use
parts cleaning solvent or water. Never use
low-flash-point solvents or gasoline to
clean the sponge material because the en-
gine could catch fire or explode.
[EWB01951]
7. Squeeze the excess water or solvent out of
the sponge material and let it dry. NOTICE:
Do not twist the sponge material when
squeezing it. Do not apply oil to the
sponge material.
[ECB00471]
1. Air filter element assembly
1. Air filter element
2. Sponge material
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88. Check the sponge material and replace it if
damaged.
9. Tap the air filter element lightly to remove
most of the dust and dirt. Blow out the remain-
ing dirt with compressed air as shown. If the
air filter element is damaged, replace it.10. Pull the sponge material over the air filter ele-
ment.
11. Insert the air filter element assembly into the
air filter case, and then install the air filter case
cover by hooking the holders. NOTICE: Make
sure that the air filter element is properly
seated in the air filter case. Never operate
the engine with the air filter element re-
moved. This will allow unfiltered air to en-
ter the engine, causing rapid engine wear
and possible engine damage. Additionally,
operation without the air filter element will
affect carburetor jetting with subsequent
poor performance and possible engine
overheating.
[ECB00461]
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8-24
8 12. Install the seat.
TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned more often if the
ATV is operated in extremely dusty areas. Each
time the air filter element maintenance is per-
formed, check the air inlet of the air filter case for
obstructions. Check the air filter case rubber joint
to the carburetor fittings and the rubber joint mani-
fold fittings for an air-tight seal. Tighten all fittings
securely to avoid the possibility of unfiltered air en-
tering the engine.EBU27082Cleaning the spark arrester Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the tailpipe bolts.2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing.
1. Tailpipe bolt
2. Tailpipe
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8-25
84. Insert the tailpipe into the muffler and align the
bolt holes.
5. Install the tailpipe bolts and tighten them to the
specified torque.
WARNING
EWB02340Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components.EBU23940Adjusting the carburetor The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to a
Yamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.
1. Tailpipe
2. Spark arresterTightening torque:
Tailpipe bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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8
NOTICEECB00480The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.EBU24000Adjusting the engine idling speed The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPA diagnostic tachometer is needed to make this
adjustment.1. Start the engine and warm it up.TIPThe engine is warm when it quickly responds to the
throttle.2. Attach the tachometer to the spark plug lead.3. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screw at the carburetor. To in-
crease the engine idling speed, turn the throt-
tle stop screw in direction (a), and to decrease
it, turn the screw in direction (b).
1. Throttle stop screwEngine idling speed:
1400–1500 r/min
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8
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.EBU24047Adjusting the throttle lever free play The throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 3.0–
5.0 mm (0.12–0.20 in) as shown. Periodically
check the throttle lever free play and, if necessary,
adjust it as follows.TIPThe engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle le-
ver free play.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24060Valve clearance The valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.1. Rubber cover
2. Locknut
3. Throttle lever free play adjusting bolt
4. Throttle lever free play
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8
EBU24071Adjusting the drive select lever safety
system cable The drive select lever safety system cable stretch-
es with use, which can result in improper function.
Therefore, the safety system cable should be
checked and adjusted by a Yamaha dealer at the
intervals specified in the periodic maintenance and
lubrication chart.EBU29601Brakes Replacement of brake components requires pro-
fessional knowledge. Brake service should be per-
formed by a Yamaha dealer.
WARNING
EWB02571Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.EBU24120Checking the front brake pads and rear
brake shoes The front brake pads and the rear brake shoes
must be checked for wear at the intervals specified
in the periodic maintenance and lubrication chart.
EBU24171Front brake pads
Check each front brake pad for damage and mea-
sure the lining thickness. If a brake pad is dam-
aged or if the lining thickness is less than 1.0 mm
(0.04 in), have a Yamaha dealer replace the brake
pads as a set.TIPThe wheels need to be removed to check the
brake pads. (See page 8-46.)1. Brake pad
2. Lining thickness
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8
EBU24180Rear brake shoes
The rear brake is provided with a wear indicator,
which allows you to check the brake shoe wear
without having to disassemble the brake. To check
the brake shoe wear, check the position of the
wear indicator while applying the brake. If a brake
shoe has worn to the point that the wear indicator
reaches the wear limit line or mark, have a
Yamaha dealer replace the brake shoes as a set.
EBU29840Checking the brake fluid level Insufficient brake fluid may allow air to enter the
brake system, possibly causing it to become inef-
fective.
Before riding, check that the brake fluid is above
the minimum level mark and replenish if neces-
sary. A low brake fluid level may indicate worn
brake pads and/or brake system leakage. If the
brake fluid level is low, be sure to check the brake
pads for wear and the brake system for leakage.
Observe these precautions:
When checking the fluid level, make sure that
the top of the brake fluid reservoir is level.
1. Wear indicator
2. Wear limit line
1. Minimum level mark
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8

Use only the recommended quality brake fluid,
otherwise the rubber seals may deteriorate,
causing leakage and poor braking performance.
Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.
Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.
Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.
As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.EBU24281Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,have the oil seals of the brake master cylinder and
calipers as well as the brake hoses replaced at the
intervals listed below or whenever they are dam-
aged or leaking.

Oil seals: Replace every two years.
Brake hoses: Replace every four years.EBU24394Checking the front brake lever free play The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever should have no
free play as shown. If there is free play, have a
Yamaha dealer check the brake system. Recommended brake fluid:
DOT 41. No brake lever free play
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8
EBU24575Adjusting the brake pedal height and
free play, and the rear brake lever free
play The brake pedal height and free play, and the
brake lever free play must be checked and, if nec-
essary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.TIP
Always perform this maintenance completely in
the following order whenever adjusting the rear
brake.
Before adjusting the brake pedal height and free
play, and the brake lever free play, check the
rear brake shoes for wear.1.Adjusting the brake pedal height
The top of the brake pedal should be posi-
tioned 43.0–53.0 mm (1.69–2.09 in) above
the top of the footboard bracket. If the height
is incorrect, adjust it as follows.a. Remove the footboard. (See “Engine oil”
on page 8-11 for removal and installation
procedures.)
b. Loosen the locknuts at the brake pedal.
c. Turn the brake pedal height adjusting bolt
at the brake pedal in direction (a) to raise
the brake pedal, and in direction (b) to low-
er it.
d. Tighten the locknuts at the brake pedal.
2.Adjusting the brake pedal free play
1. Locknut
2. Brake pedal height adjusting bolt
3. Brake pedal height
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