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8
14. Install the washer onto the air filter element
frame, and then insert the wing bolt into the
hole in the air filter element frame. NOTICE:
Be sure to install the washer with its
curved side facing outward as shown.
[ECB00454]
15. Insert the air filter element into the air filter case, and then tighten the wing bolt.
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. Doing so would al-
low unfiltered air to enter the engine, caus-
ing rapid engine wear and possible engine
damage. Additionally, the fuel injection
system would be affected resulting in poor
engine performance and possible over-
heating.
[ECB00763]
16. Install the air filter case cover by hooking the holders onto the air filter case.
1. Air filter element seat
1
1. Washer
1
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8-26
817. 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 throttle body and the rub-
ber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU30861Cleaning the spark arresterSelect a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the tailpipe cover by removing the bolts. 2. Remove the retainer by removing the bolts,
and then remove the tailpipe and gasket from
the muffler.
1. Tailpipe cover
2. Bolt
2
2
1
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8-27
8
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. Install the gasket, tailpipe, and retainer and
align the bolt holes.
5. Install the bolts and tighten them to the spec- ified torque.
6. Install the tailpipe cover and align the bolt holes.
7. Install the bolts and tighten them to the spec- ified torque.
1. Bolt
2. Retainer
3. Tailpipe
4. Gasket1
2
3
4
1
1. Tailpipe
2. Spark arresterTightening torque:Retainer bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
2
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8-28
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. EBU26812Adjusting 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.
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
idle adjusting screw. To increase the engine
idling speed, turn the idle adjusting screw in
direction (a), and to decrease it, turn the
screw in direction (b).
Tightening torque:
Tailpipe cover bolt:8 N·m (0.8 kgf·m, 5.9 lb·ft)
1. Idle adjusting screwEngine idling speed:1500–1700 r/min
1
(a)
(b)
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8-29
8
TIPIf the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment. EBU24049Adjusting the throttle lever free play
Periodically check the throttle lever free play and
adjust if necessary.TIPThe engine idling speed must be checked and ad-
justed 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, turnthe 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.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.
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playThrottle lever free play: 2.0–4.0 mm (0.08–0.16 in)
32
4
(a)(b)
1
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8-30
8
EBU24081Adjusting the reverse lock release ca-
bleThe reverse lock release cable stretches with use,
which can result in improper function. Therefore,
the reverse lock release cable should be checked
and adjusted at the intervals specified in the peri-
odic 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. EBU24131Checking the front and rear brake padsThe front and rear brake pads must be checked
for wear at the intervals specified in the periodic
maintenance and lubrication chart.
EBU29561Front brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves have almost dis-
appeared, have a Yamaha dealer replace the
brake pads as a set.TIPThe wheels need to be removed to check the
brake pads. (See page 8-53.) 1. Wear indicator groove
1
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8
EBU29832Rear brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves have almost dis-
appeared, have a Yamaha dealer replace the
brake pads as a set.
EBU26829Checking 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.
Front brake (YFM70RSBJ)
1. Wear indicator groove
1
1. Minimum level mark
1
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8-32
8(YFM70RSXJ)
Rear brake
TIPTo check the rear brake fluid level, remove the
seat. (See page 4-11.) To access the rear brake fluid reservoir for replen-
ishing:
1. Remove the bolt and quick fastener screw.
2. Pull the cowling slightly outward as shown.
1. Minimum level mark
1. Minimum level mark
11
1. Quick fastener screw
2. Bolt
1
2
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