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8
8. Check the sponge material and replace it if
damaged.
9. Apply Yamaha foam air filter oil or other qual- ity foam air filter oil to the sponge material.
TIPThe sponge material should be wet but not drip-
ping. 10. Pull the sponge material over the air filter ele- ment frame, and then install the lock plate.
11. Insert the air filter element into the air filter case, and then install the air filter case cover
by hooking the holders onto the air filter case.
NOTICE: Make sure that the air filter ele-
ment is properly seated in the air filter case. Never operate the engine with the air
filter element removed. This will allow un-
filtered air to enter 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.
[ECB00462]
12. Install the seat.TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated
more often if the ATV is operated in extremely
dusty areas. Each time the air filter element main-
tenance is performed, 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 manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU27083Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the tailpipe bolts.
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8-23
82. 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. 4. Insert the tailpipe into the muffler and align
the bolt holes.
5. Install the tailpipe bolts and tighten them to the specified torque.
1. Tailpipe bolt
2. Tailpipe
1. Tailpipe
2. Spark arresterTightening torque:Tailpipe bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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8-24
8
WARNING
EWB02341Do 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. EBU23921V-belt cooling duct check hoseIf dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
EBU23932V-belt case drain plugAfter riding in water deep enough to allow it to en-
ter the V-belt case, remove the V-belt case drain
plug to drain the water from the case.TIPIf water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.
1. V-belt cooling duct check hose (left front side of ATV)
1. V-belt case drain plug
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8
EBU23941Adjusting the carburetorThe carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the pe-
riodic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. There-
fore, most carburetor adjustments should be left
to a Yamaha dealer, who has the necessary pro-
fessional knowledge and experience. The adjust-
ment described in the following section, however,
may be performed by the owner as part of routine
maintenance.NOTICEECB00481The 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. EBU24001Adjusting the engine idling speedThe 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).
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8
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment. EBU24048Adjusting the throttle lever free playThe 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
adjusted if necessary, before adjusting the throttle
lever 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).
1. Throttle stop screwEngine idling speed:1450–1550 r/min
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8-27
84. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24061Valve clearanceThe 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.
EBU24072Adjusting the drive select lever safety
system cableThe 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.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
1. Throttle lever free play
2. Rubber cover
3. Locknut
4. Throttle lever free play adjusting bolt2
4 3
1
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8
EBU24121Checking the front brake pads and rear
brake shoesThe front brake pads and the rear brake shoes
must be checked for wear at the intervals speci-
fied in the periodic maintenance and lubrication
chart.EBU24172Front 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.) EBU24181Rear 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 a1. Brake pad
2. Lining thickness
2
1
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8-29
8brake shoe has worn to the point that the wear in-
dicator reaches the wear limit line or mark, have a
Yamaha dealer replace the brake shoes as a set.
EBU29843Checking the brake fluid levelBefore riding, check that the brake fluid is above
the minimum level mark. Check the brake fluid lev-
el with the top of the reservoir level. Replenish the
brake fluid if necessary.
WARNING
EWB02721Improper maintenance can result in loss of
braking ability. Observe these precautions:
Insufficient brake fluid may allow air to enter
the brake system, reducing braking perfor-
mance.
Clean the filler cap before removing. Use
only DOT 4 brake fluid from a sealed contain-
er.
1. Wear limit line
2. Wear indicator
1
2
1. Minimum level markSpecified brake fluid: DOT 4
1
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