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ter or salt water since it is harmful to the en-
gine.
If water has been used instead of coolant, re-
place it with coolant as soon as possible,
otherwise the cooling system will not be pro-
tected against frost and corrosion.
If water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant will
be reduced.
6. Close the coolant reservoir cover.
7. Install the seat.
TIP
If the engine overheats, see page 8-52 for further
instructions.
EBU23521
To change the coolant
WARNING
EWB01890
Wait for the engine and radiator to cool before
removing the radiator cap. You could be
burned by hot fluid and steam blown out under
pressure. Always place a thick rag over the capwhen opening. Allow any remaining pressure
to escape before completely removing the cap.
1. Place the ATV on a level surface.
2. Remove the radiator cover by removing the
bolts.
3. Place a container under the engine and re-
move the coolant drain bolts.
1. Radiator cover
2. Radiator cover bolt
12
2
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voir to the maximum level mark, and then in-
stall the reservoir cap.
11. Pour the recommended coolant into the radia-
tor until it is full.
NOTICE
ECB00401
If coolant is not available, use distilled water
or soft tap water instead. Do not use hard wa-
ter or salt water since it is harmful to the en-
gine.
If water has been used instead of coolant, re-
place it with coolant as soon as possible,
otherwise the cooling system will not be pro-tected against frost and corrosion.
If water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant will
be reduced.
12. Install the radiator cap, start the engine, let it
idle for several minutes, and then turn it off.
13. Remove the radiator cap to check the coolant
level in the radiator. If it is low, add sufficient
coolant until it reaches the top of the radiator,
and then install the radiator cap.
14. Start the engine, and then check for coolant
leakage.
TIP
If any leakage is found, have a Yamaha dealer
check the cooling system.
15. Install the radiator cover by installing the bolts.
EBU23622
Cleaning the air filter element
The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dusty Antifreeze/water mixture ratio:
1:1
Recommended antifreeze:
High-quality ethylene glycol antifreeze con-
taining corrosion inhibitors for aluminum en-
gines
Coolant quantity:
Radiator capacity (including all routes):
1.50 L (1.59 US qt, 1.32 Imp.qt)
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.28 L (0.30 US qt, 0.25 Imp.qt)
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5. Remove the lock plate by turning it, and then
remove the sponge material from the air filter
element frame.6. Wash the sponge material gently but thor-
oughly in solvent.
WARNING
EWB01940
Always use parts cleaning solvent to clean the
sponge material. Never use low-flash-point
solvents or gasoline to clean the sponge mate-
rial because the engine could catch fire or ex-
plode.
7. Squeeze the excess solvent out of the sponge
material and let it dry.
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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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.
NOTICE
ECB00460
Make sure that the air filter element is prop-
erly seated in the air filter case.
Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addition-
ally, operation without the air filter element
will affect carburetor jetting with subsequent
poor performance and possible engine over-
heating.
EBU28310
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.
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.
EBU23992
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-
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-
1. Tailpipe
2. Spark arrester
3. Gasket
1
2
3
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5. Move the throttle lever a few times and re-
check the position.
6. Install the fuel tank, side cover, radiator cover
and air filter case cover.
7. Connect the fuel hoses.
8. Install the seat.
EBU24020
Adjusting 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.
TIP
A diagnostic tachometer is needed to make this
adjustment.
The carburetor synchronization and the throttle
cable free play must be checked, and adjusted if
necessary, before adjusting the engine idling
speed.
1. Start the engine and warm it up.
TIP
The engine is warm when it quickly responds to the
throttle.
2. Attach the tachometer to the spark plug lead.
3. Turn in both pilot air screws until they lightly
seat.
4. Turn out both pilot air screws to specification.
(See the “Changing the carburetor settings”
section on the page 8-22.)
1. Adjusting nut
2. Locknut
1
2
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5. Remove the seat. (See page 4-11.)
6. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screws at the carburetors. To in-
crease the engine idling speed, turn the throt-
tle stop screws in direction (a), and to
decrease it, turn the screws in direction (b).NOTICE
ECB00510
The throttle stop screws were preset at the
factory. When adjusting the idling speed,
turn both throttle stop screws the same
amount, otherwise the carburetor synchroni-
zation will be incorrect.
Adjusting the pilot air screws and the idling
speed are separate procedures, but they
must be adjusted at the same time to achieve
1. Pilot air screw
1
1. Throttle stop screw
Engine idling speed:
1450–1550 r/min
1
(b)
(a)
(a)
(b)
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optimum engine performance.
TIP
If the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.
7. Install the seat.
EBU24044
Adjusting the throttle cable free play
The throttle cable free play should be checked
and, if necessary, adjusted at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
The throttle cable free play should measure 4.0–
6.0 mm (0.16–0.24 in) at the throttle lever. Period-
ically check the throttle cable free play and, if nec-
essary, adjust it as follows.
TIP
The engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-
ble free play.
1. Loosen the locknut.
2. To increase the throttle cable free play, turn
the throttle cable free play adjusting bolt in di-rection (a). To decrease the throttle cable free
play, turn the adjusting bolt in direction (b).
3. Tighten the locknut.
EBU24130
Checking the front and rear brake pads
The front and rear brake pads must be checked for
wear at the intervals specified in the periodic main-
tenance and lubrication chart.
1. Throttle lever free play adjusting bolt
2. Locknut
3. Throttle cable free play
1
2
3
(a)(b)
