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8-17
8To install the panel
1. Connect the coupler, and then place the pan-
el in the original position.
2. Install the quick fasteners.
3. Place the carrier in the original position, and then install the carrier bolts under the fenders.
4. Install the carrier top bolts, and then tighten all bolts to the specified torques. 5. Install the cover.
For YFM45KPXK / YFM45KPHK /
YFM45KPLK: Install the handlebar-mount-
ed light cover.
For YFM45KDXK / YFM45KDHK: Install
the handlebar cover.
6. Install the panels.
EBU23215Checking the spark plugThe spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the
spark plug should be removed and checked in ac-
cordance with the periodic maintenance and lubri-
cation chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug 1. Remove the spark plug cap.
Tightening torques: Carrier bolt (top):34 N·m (3.4 kgf·m, 25 lb·ft)
Carrier bolt (under fenders): 7 N·m (0.7 kgf·m, 5.2 lb·ft)
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8-19
8To install the spark plug
1. Clean the surface of the spark plug gasket and its mating surface, and then wipe off any
grime from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tighten it to the specified
torque.
TIPIf a torque wrench is not available when installing
the spark plug, a good estimate of the correct
torque is 1/4–1/2 turn past finger tight. However,
the spark plug should be tightened to the speci-
fied torque as soon as possible. 3. Install the spark plug cap.EBU30245Engine oil and oil filter cartridgeThe engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals
specified in the periodic maintenance chart.
To check the engine oil level1. Park the ATV on a level surface.
2. Remove panel E. (See page 8-10.)
3. Check the engine oil level on a cold engine.
1. Spark plug gapSpark plug gap: 0.6–0.7 mm (0.024–0.028 in)
Tightening torque:Spark plug:18 N·m (1.8 kgf·m, 13 lb·ft)
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8
13. Check the engine oil filler cap O-ring for dam-
age, and then install the filler cap.
14. Start the engine and let it idle for several min- utes while checking for oil leakage. If any oil
leakage is found, immediately turn the engine
off and check for the cause.
15. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
16. Install panel E.
EBU28568Final 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 level 1. Park 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. 3. If the oil is below the brim of the filler hole, add
sufficient oil of the recommended type to
raise it to the correct level.
4. Check the oil filler bolt gasket for damage, and replace it if necessary.
5. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
1. Final gear oil filler bolt
2. Gasket
3. Final gear oil
4. Correct oil levelTightening torque:Final gear oil filler bolt:22 N·m (2.2 kgf·m, 16 lb·ft)1
2
3
4
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8
EBU23439Changing 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. Park 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. 4. 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]
1. Differential gear oil filler bolt
2. Gasket
21
1. Differential gear oil drain bolt
2. GasketTightening torque: Differential gear oil drain bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
12
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8
TIPDo 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.
EBU23472CoolantThe coolant level should be checked regularly. In
addition, the coolant must be changed at the in-
tervals specified in the periodic maintenance and
lubrication chart.TIPIf genuine Yamaha coolant is not available, use an
ethylene glycol antifreeze containing corrosion in-
hibitors for aluminum engines and mix with dis-
tilled water at a 1:1 ratio.
Recommended differential gear oil:Yamaha Friction Modified Shaft Drive Gear Oil or SAE 80 API GL-4 Hypoid gear oil
Oil quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)
Tightening torque: Differential gear oil filler bolt:23 N·m (2.3 kgf·m, 17 lb·ft)
Recommended coolant:YAMALUBE coolant
Coolant quantity: Coolant reservoir (up to full level):0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator (including all routes): 1.32 L (1.40 US qt, 1.16 Imp.qt)
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8
EBU29704Adjusting the throttle lever free playPeriodically check the throttle lever free play and
adjust if necessary.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.
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.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 boltThrottle lever free play: 3.0–5.0 mm (0.12–0.20 in)2
4 3
1
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8
EBU28414Checking the front brake pads and rear
brake friction platesThe front brake pads and the rear brake friction
plates must be checked for wear at the intervals
specified in the periodic maintenance and lubrica-
tion chart.TIPThis ATV is equipped with a wet, multiple-disc
type rear brake, which is located inside of the final
gear case. EBU24174Front brake padsCheck each front brake pad for damage and mea-
sure the lining thickness. If a brake pad is dam-
aged or if the lining thickness reaches the
specified limit, have a Yamaha dealer replace the
brake pads as a set.
TIPThe wheels need to be removed to check the
brake pads. (See page 8-63.) EBU30321Rear brake friction plates
The rear brake friction plates must be checked
and, if necessary, replaced by a Yamaha dealer at
the intervals specified in the periodic maintenance
and lubrication chart.EBU29844Checking the brake fluid levelBefore riding, check that the brake fluid is above
the minimum level mark. Replenish the brake fluid
if necessary.
1. Lining thickness
Brake pad lining thickness limit:
1.0 mm (0.04 in)
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8
TIPStraighten the handlebars for an accurate reading. NOTICEECB01161Brake fluid may damage painted surfaces or
plastic parts. Always clean up spilled fluid im-
mediately.
As the brake pads wear, it is normal for the brake
fluid level to gradually go down. A low brake fluid
level may indicate worn brake pads or brake sys-
tem leakage. Therefore, be sure to check the
brake pads for wear and the brake system for
leakage. If the brake fluid level suddenly goes
down, have a Yamaha dealer the brake system
before further riding.
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.
Use only the specified brake fluid; otherwise,
the rubber seals may deteriorate, causing
leakage.
Refill with the same type of brake fluid. Add-
ing a brake fluid other than DOT 4 may result
in a harmful chemical reaction.
1. Minimum level markSpecified brake fluid:
DOT 4
1
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