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8-23
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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8-26
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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8-27
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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8-31
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.TIPAlways 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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8-34
8 d. Tighten the locknut at the brake lever.
e. Install the footboard.
TIPWhen adjusting the rear brake lever free play:Be sure not to step on the brake pedal.Make sure the brake pedal does not move.EBU24762Brake light switches The brake light, which is activated by the brake
pedal and brake levers, should come on just be-
fore braking takes effect.The brake light switch for the brake pedal can be
adjusted as follows, but the other brake light
switches should be adjusted by a Yamaha dealer.
1. Remove the footboard. (See “Engine oil” on
page 8-11 for removal and installation proce-
dures.)
2. Turn the adjusting nut while holding the brake
light switch in place. To make the brake light
come on earlier, turn the adjusting nut in direc-
tion (a). To make the brake light come on lat-
er, turn the adjusting nut in direction (b).
3. Install the footboard.1. Locknut
2. Brake lever free play adjusting bolt
1. Rear brake light switch
2. Rear brake light switch adjusting nut
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8-35
8
EBU24803Adjusting the clutch free play The clutch free play must be adjusted periodically.
Adjust the free play as follows.
1. Remove the footboard. (See “Engine oil” on
page 8-11 for removal and installation proce-
dures.)
2. Loosen the locknut.
3. Slowly turn the clutch adjusting screw in direc-
tion (a) until resistance is felt, and then turn it
1/8 turn in direction (b).
TIPTurning the clutch adjusting screw in direction (a)
decreases clutch free play and turning it in direc-
tion (b) increases clutch free play.4. Tighten the locknut to the specified torque.TIPWhen tightening the locknut, hold the clutch ad-
justing screw with a screwdriver so that it does not
turn together with the locknut.5. Install the footboard.EBU24901Checking and lubricating the cables The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
1. Locknut
2. Clutch adjusting screw
Tightening torque:
Locknut:
15 Nm (1.5 m·kgf, 11 ft·lbf)
U1P066E0.book Page 35 Thursday, August 5, 2010 4:15 PM