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8-13
8 Before installing the spark plug, the spark plug gap
should be measured with a wire thickness gauge
and, if necessary, adjusted to specification.
Clean the surface of the spark plug gasket and its
mating surface, and then wipe off any grime from
the spark plug threads.
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 specified
torque as soon as possible.EBU29498Engine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Start the engine, warm it up until the engine oil
has reached a normal temperature of 40 °C
(104 °F), let it continue to idle for ten seconds
or more, and then turn the engine off. Specified spark plug:
NGK/CR8E
1. Spark plug gapSpark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Tightening torque:
Spark plug:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
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8-14
8
TIPTo achieve the proper engine oil temperature for
an accurate oil level reading, the engine must have
first completely cooled down, and then warmed up
again for several minutes to normal operating tem-
perature.3. Remove the engine oil tank filler cap, and
wipe the engine oil dipstick off with a clean
rag.
4. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.TIPThe engine oil should be between the minimum
and maximum level marks.
5. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type through the engine oil tank filler
hole to raise it to the correct level. NOTICE:
Be sure the engine oil is at the correct lev-
el, otherwise engine damage may result.
[ECB00851]
1. Engine oil tank filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Half-level mark
5. Minimum level mark11
2
3
54
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8-15
8
TIPWhen adding oil, be careful not to overfill the en-
gine oil tank; the oil level rises faster starting from
the half-level-portion on the dipstick.6. Insert the dipstick into the engine oil tank filler
hole, and then tighten the engine oil tank filler
cap. NOTICE: Make sure that the engine oil
tank filler cap is securely tightened; other-
wise, oil may seep out when the engine is
running.
[ECB00362]
To change the engine oil (with or without oil fil-
ter element replacement)
1. Place the ATV on a level surface.
2. Remove the engine guard by removing the
bolts.3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Place an oil pan under the engine to collect
the used oil.
5. Remove the engine oil tank filler cap, and then
remove the engine oil tank drain bolt and its
gasket.
1. Engine guard
2. Bolt
221
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8-16
86. Remove the crankcase engine oil drain bolt
and its gasket.
TIPSkip steps 7–10 if the oil filter element is not being
replaced.7. Remove the oil filter element cover by remov-
ing the bolts.
1. Engine oil tank drain bolt
2. Gasket
1
2
1. Crankcase engine oil drain bolt
2. Gasket
12
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8-17
8 8. Remove the oil filter element and the O-rings.
9. Install a new oil filter element and new O-
rings.
TIPMake sure that the O-rings are properly seated.10. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
1. Oil filter element cover
2. Bolt
1
2
1. Oil filter element
2. O-ringTightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
2
2
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8-18
811. Install the crankcase engine oil drain bolt, the
engine oil tank drain bolt and their new gasket,
and then tighten the bolts to their specified
torques.
12. Refill with the specified amount of the recom-
mended engine oil through the engine oil tank
filler hole, and then install and tighten the en-
gine oil tank filler cap.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.NOTICEECB00300In 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.13. 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.
14. Turn the engine off, and then check the oil lev-
el and correct it if necessary. Tightening torques:
Crankcase engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Engine oil tank drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
1.40 L (1.48 US qt, 1.23 Imp.qt)
With oil filter element replacement:
1.45 L (1.53 US qt, 1.28 Imp.qt)
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8-23
8 10. Check the sponge material and replace it if
damaged.
11. Apply Yamaha foam air filter oil or other qual-
ity foam air filter oil to the sponge material.
TIPThe sponge material should be wet but not drip-
ping.12. Pull the sponge material over the air filter ele-
ment frame.
13. Apply all-purpose grease to the air filter ele-
ment seat.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.
[ECB00453]
1. Air filter element seat
1
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8-30
8
Refill with the same type of brake fluid. Mixing
fluids may result in a harmful chemical reaction
and lead to poor braking performance.Be careful that water does not enter the brake
fluid reservoir when refilling. Water will signifi-
cantly lower the boiling point of the fluid and may
result in vapor lock.Brake fluid may deteriorate painted surfaces or
plastic parts. Always clean up spilled fluid imme-
diately.As the brake pads wear, it is normal for the brake
fluid level to gradually go down. However, if the
brake fluid level goes down suddenly, have a
Yamaha dealer check the cause.EBU24291Changing the brake fluid Have a Yamaha dealer change the brake fluid at
the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,
have the oil seals of the master cylinders and cali-
pers as well as the brake hoses replaced at the in-
tervals listed below or whenever they are damaged
or leaking.Oil seals: Replace every two years.Brake hoses: Replace every four years.
EBU24394Checking the front brake lever free play The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever should have no
free play as shown. If there is free play, have a
Yamaha dealer check the brake system.EBU24613Checking the brake pedal height The brake pedal height must be checked and, if
necessary, adjusted at the intervals specified in the
periodic maintenance and lubrication chart.1. No brake lever free play
1
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