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8-15
89. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down. NOTICEECB00301In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD” or oils of
a higher quality than specified. In addition,
do not use oils labeled “ENERGY CONSERV-
ING II” or higher.
Make sure that no foreign material enters the
crankcase.
10. Start the engine, and then let it idle for several
minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
11. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.EBU23387Final gear oilThe final gear case must be checked for oil leak-
age before each ride. If any leakage is found, have
a Yamaha dealer check and repair the ATV. In ad-
dition, the final gear oil level must be checked and
the oil changed as follows at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
To check the final gear oil level1. Place the ATV on a level surface.
2. Remove the final gear oil filler bolt and its gas- ket, and then check the oil level in the final
gear case. The oil level should be at the brim
of the filler hole.
Recommended oil:
See page 10-1.
Oil quantity: Without oil filter cartridge replacement:2.20 L (2.33 US qt, 1.94 Imp.qt)
With oil filter cartridge replacement: 2.30 L (2.43 US qt, 2.02 Imp.qt)
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8
9. Check the final gear case for oil leakage. If oil
is leaking, check for the cause.
10. Install the final gear case guard by installing the bolts and tightening them to the specified
torque.
EBU23437Changing the differential gear oilThe differential gear case must be checked for oil
leakage before each ride. If any leakage is found,
have a Yamaha dealer check and repair the ATV.
In addition, the differential gear oil must be
changed as follows at the intervals specified in the
periodic maintenance and lubrication chart.1. Place the ATV on a level surface.
2. Place an oil pan under the differential gear case to collect the used oil.
3. Remove the differential gear oil filler bolt, the differential gear oil drain bolt and their gasket
to drain the oil from the differential gear case.
Tightening torque:
Final gear case guard bolt:16 Nm (1.6 m·kgf, 12 ft·lbf)
1. Differential gear oil filler bolt
2. Gasket
1. Differential gear oil drain bolt
2. Gasket
21
12
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8-19
84. Install the drain bolt and its new gasket, and
then tighten the bolt to the specified torque.
5. Refill with the specified amount of the recom- mended differential gear oil. NOTICE: Be
sure no foreign material enters the differ-
ential gear case.
[ECB00412]
TIP Do not exceed the specified differential gear oil
quantity when filling. Overfilling will cause the oil
to seep out of the breather hose during and af-
ter riding.
The differential gear case capacity is greater
than the recommended oil quantity, therefore
the oil level cannot be accurately checked from
the oil filler hole.
6. Check the oil filler bolt gasket for damage,
and replace it if necessary.
7. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
8. Check the differential gear case for oil leak- age. If oil is leaking, check for the cause.EBU23647Cleaning the air filter elementThe air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean or, if necessary, replace
the air filter element more frequently if you are rid-
ing in unusually wet or dusty areas.TIPThere is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case.
Tightening torque:Differential gear oil drain bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Recommended differential gear oil: See page 10-1.
Oil quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)
Tightening torque:Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)
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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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