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1. Place the ATV on a level surface.
2. Remove the seat. (See page 4-11.)
3. Remove the air filter case cover by unhooking
the holders.4. Pull the air filter element out of the air filter
case.
5. Remove the lock plate by turning it, and then
remove the sponge material from the air filter
element frame.
1. Air filter case check hose
1
1. Air filter case cover
2. Air filter case cover holder
1 2 2
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6. Wash the sponge material gently but thor-
oughly in solvent.
WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01941]
7. Squeeze the excess solvent out of the sponge
material and let it dry.
NOTICE:
Do not twist
the sponge material when squeezing
it.
[ECB00441]
1. Air filter element lock plate
1
1. Sponge material
2. Air filter element frame
3. Air filter element lock plate
1 22
1
3
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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.
TIP
The 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 by
turning it.
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 rap-
id 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]
12. Install the seat.
TIP
The air filter element should be cleaned every 20–
1. Air filter element
1
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40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
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 fit-
tings securely to avoid the possibility of unfiltered
air entering the engine.
EBU28311
Cleaning the spark arrester
Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the screws.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. Screw
1
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4. Make sure the gasket is properly positioned,
then insert the tailpipe into the muffler and
align the screw holes.
5. Install the screws and tighten them to the
specified torque.
WARNING
EWB02340
Do 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.
EBU23994
Changing the carburetor settings
In extremely cold weather, it is necessary to
change the carburetor settings to maintain opti-
mum engine performance and to prevent engine
damage.WARNING
EWB01990
Improperly servicing or adjusting the carbu-
retors could cause them to malfunction with
the possibility of an accident, or the carbure-
tors could leak fuel, which would be a fire
hazard.
Carburetor adjustments should only be per-
formed by a Yamaha dealer. Do not attempt
to perform these procedures unless you
have mechanical knowledge and the neces-
1. Screw
2. Tailpipe
3. Spark arrester
4. Gasket
Tightening torque:
Screw:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
2
3
41
1
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sary tools.
Do not perform this procedure while the en-
gine is hot. Place a rag under each carbure-
tor to catch any fuel. Wipe up any spilled fuel
completely.
After servicing the carburetors, always
check the throttle lever operation before op-
erating the ATV to make sure it is working
correctly.
Standard settings
Main jet #200
Jet needle clip position 3rd groove
Pilot air screw 2.0 turns out
1. Main jet number
1
1. Standard position: Groove 3
1
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Carburetor setting chart
Changing the settings of the carburetors
To change the settings of the carburetors, you
need to disassemble and remove them. Follow the
procedures for both carburetors.
Disassembling and removing the carburetors
1. Turn the fuel cock to the “OFF” position.
2. Turn out the carburetor drain screw to drain
the fuel.
3. Remove the seat.
4. Remove the radiator cover and side cover by
removing the screws.
5. Remove the fuel hose from the fuel cock.
TemperatureAltitude
0
–1500 m (5000 ft) Above 1500 m (5000 ft)
Main jet Jet needle Pilot air screw Main jet Jet needle Pilot air screw
Above 0 °C (32 °F) #200 3rd groove 2.0 turns out #190 3rd groove 2 1/2 turns out
from +5 °C (41 °F) to
–15 °C (5 °F)#220 3rd groove 1 1/2 turns out #200 3rd groove 2.0 turns out
from –10 °C (14 °F) to
–30 °C (–22 °F)#240 4th groove 1 1/2 turns out #220 3rd groove 1 1/2 turns out
1. Radiator cover
2. Side cover
3. Screw
1
2 3 3
3
3
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6. Remove the fuel tank by removing the bolts.
7. Remove the air filter case cover by unhooking
the holders.
1. Fuel hose
1
1. Fuel tank
2. Bolt
1
2
22
2