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8-7
8
EBU28130TIPThe air filter needs more frequent service if you are riding in unusually wet or dusty areas.Hydraulic brake service
Regularly check and, if necessary, correct the brake fluid level.
Every two years replace the internal components of the brake master cylinders and calipers, and
change the brake fluid.
Every two years replace the piston seals and O-ring of the brake equalizer.Replace the brake hoses every four years and if cracked or damaged.21*Moving parts and
cablesLubricate.√√√√
22*Throttle lever hous-
ing and cableCheck operation and correct if necessary.
Check throttle cable free play and adjust if neces-
sary.
Lubricate throttle lever housing and cable.√√√√√
23*Front and rear brake
switchesCheck operation and correct if necessary.√√√√√
24*Lights and switchesCheck operation and correct if necessary.
Adjust headlight beam.√√√√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320U33B70E0.book Page 7 Wednesday, June 11, 2008 1:38 PM
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8-8
8
EBU23211Checking the spark plug The 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 accor-
dance with the periodic maintenance and lubrica-
tion 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.
2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-stead, have a Yamaha dealer check the ATV.
2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
1. Spark plug cap
1
1. Spark plug wrench
1
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8-9
8 To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.3. 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
a 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 assoon as possible.
4. Install the spark plug cap.EBU28953Engine 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 must be replaced at the inter-
vals specified in the periodic maintenance and lu-
brication chart.
To check the engine oil level
1. Place the ATV on a level surface. Specified spark plug:
NGK/DR7EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gap
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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8-10
82. Check the engine oil level on a cold engine.
TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-tles for an accurate reading.
3. Remove the engine oil filler cap, and then
wipe the 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 minimumand maximum level marks.
5. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
To change the engine oil (with or without oil fil-
ter element replacement)
1. Start the engine, warm it up for several min-
utes, and then turn it off.
2. Place an oil pan under the engine to collect
the used oil.
3. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
1
2
3
4 1
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8-11
8
TIPSkip steps 4–7 if the oil filter element is not beingreplaced.
4. Remove the oil filter element cover by remov-
ing the bolts, and then remove the oil filter el-
ement.5. Check the O-rings for damage and replace
them if necessary.1. Engine oil drain bolt
1
1. Oil filter element cover
2. Bolt
1 2
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8-12
86. Install a new oil filter element.
TIPMake sure that the O-rings are properly seated.
7. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
8. Install the engine oil drain bolt and tighten it to
the specified torque.9. 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 theengine 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
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
Tightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
1.25 L (1.32 US qt, 1.10 Imp.qt)
With oil filter element replacement:
1.35 L (1.43 US qt, 1.19 Imp.qt)
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8-13
8 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 thecrankcase.
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.
EBU23704Cleaning the air filter element The 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
riding 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.
1. Place the ATV on a level surface.
1.“CD” specification
2.“ENERGY CONSERVING II”
1
2
1. Air filter case check hose
1
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8-14
82. Remove the seat. (See page 4-14.)
3. Remove the air filter case cover by unhooking
the holders.
4. Loosen the wing bolt.
5. Remove the air filter element together with the
wing bolt and washer.6. Remove the wing bolt and washer from the air
filter element.
7. Remove the sponge material from the air filter
element frame.
1. Air filter case cover
2. Air filter case cover holder
12
1. Wing bolt
2. Air filter element
1 2
U33B70E0.book Page 14 Wednesday, June 11, 2008 1:38 PM