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8
4. Install the differential gear oil drain boltand its new gasket, and then tighten the
bolt to the specified torque.
5. Refill the differential gear case with the recommended oil. NOTICE: Be sure no
foreign material enters the differential
gear case.
[ECB00412]
TIP GL-4 is a quality and additive rating; GL-5
rated hypoid gear oils may also be used.
If desired, an SAE 80W-90 hypoid gear oil
may be used instead.
6. Check the oil filler bolt gasket for dam-
age, and replace it if necessary.
7. Install the differential gear oil filler bolt and its gasket, and then tighten the bolt
to the specified torque.
8. Check for oil leakage. If oil leakage is found, check for the cause.EBU35110CoolantCheck the coolant level prior to each time you
operate the vehicle, and have a Yamaha deal-
er change the coolant every two years.
Checking the coolant level
1. Park the vehicle on a level surface.
2. Remove the hood. (See page 8-10.)
Tightening torque: Differential gear oil drain bolt:9.8 N·m (0.98 kgf·m, 7.1 lb·ft)
Recommended oil: SAE 80 API GL-4 Hypoid gear oil
Oil quantity: 0.18 L (0.19 US qt, 0.16 Imp.qt)
Tightening torque: Differential gear oil filler bolt:23 N·m (2.3 kgf·m, 17 lb·ft)
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3. Check the coolant level when the engineis cold (the coolant level will vary with en-
gine temperature).TIPThe coolant level in the coolant reservoir
should be between the minimum and maxi-
mum level marks. 4. If the coolant level is at or below the mini-
mum level mark, remove the coolant res-
ervoir cap and add coolant to the maximum level mark.
NOTICE: If cool-
ant is not available, use distilled water
or soft tap water instead. Do not use
hard water or salt water since they are
harmful to the engine. If water has
been used instead of coolant, replace
it with coolant as soon as possible,
otherwise the cooling system will not
be protected against frost and corro-
sion. If water has been added to the
coolant, have a Yamaha dealer check
the antifreeze content of the coolant
as soon as possible, otherwise the ef-
fectiveness of the coolant will be re-
duced.
[ECB01012]
5. Install the reservoir cap.
6. Install the hood when finished servicing
the vehicle.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
1
32
Coolant reservoir capacity
(up to the maximum level mark):0.31 L (0.33 US qt, 0.28 Imp.qt)
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8
TIPThe radiator fan automatically switches on
or off according to the temperature of the
coolant in the radiator.
If the engine overheats, see page 8-67 for
instructions. EBU32400Axle bootsCheck the axle boots for holes or tears.
If any damage is found, have them replaced
by a Yamaha dealer.
EBU35121Checking the spark plugsThe spark plug is an important engine com-
ponent which should be periodically
checked, preferably by a Yamaha dealer.
Since heat and deposits will cause any spark
plug to slowly erode, the spark plugs should
be removed and checked in accordance with
the periodic maintenance chart for the emis-
sion control system. In addition, the condition
of the spark plugs can reveal the condition of
the engine.
1. Front axle boot
1
1
1. Rear axle boot
1
1
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The porcelain insulator around the center
electrode of each spark plug should be a me-
dium-to-light tan color (the ideal color when
the vehicle is ridden normally), and all spark
plugs installed in the engine should have a
similar color. If any spark plug shows a dis-
tinctly different color, the engine could be op-
erating improperly. Do not attempt to
diagnose such problems yourself. Instead,
have a Yamaha dealer check the vehicle.
If a spark plug shows signs of electrode ero-
sion and excessive carbon or other deposits,
it should be replaced.
Before installing a spark plug, the spark plug
gap should be measured with a wire thick-
ness 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.Specified spark plug:
NGK/CR9EB
1. Spark plug gapSpark plug gap:0.7–0.8 mm (0.028–0.031 in)
Tightening torque: Spark plug:13 N·m (1.3 kgf·m, 9.4 lb·ft)
1
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TIPIf a torque wrench is not available when in-
stalling 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. NOTICEECB02900Do not use any tools to remove or install
the spark plug cap, otherwise the ignition
coil coupler may be damaged. The spark
plug cap may be difficult to remove be-
cause the rubber seal on the end of the cap
fits tightly. To remove the spark plug cap,
simply twist it back and forth while pulling
it out; to install it, twist it back and forth
while pushing it in.
EBU35423Air filter maintenanceThis model is equipped with two air filter ele-
ments, a primary foam-type air filter and a
secondary paper-type air filter.
The primary air filter is easily accessed and
should be cleaned and oiled every 300–600
km (200–400 mi).
The secondary air filter is more difficult to ac-
cess, cannot be cleaned, and should be re-
placed by a Yamaha dealer every 2000–5000
km (1200–3000 mi).1. Primary air filter
2. Secondary air filter
1
2
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TIPService the air filters more frequently when
operating in wet or dusy environments. Whenever air filter maintenance is performed:
check the air inlet for obstructions and the
air filter case for dirt and foreign matter.
check the air filter case check hoses for dirt
or water and clean as necessary.
check the air filter cas e joints and the rub-
ber joints to and from the throttle body for
proper fit and sealing.
tighten all fittings securely to avoid the pos-
sibility of unfiltered air entering the engine.NOTICEECB02270Never operate the engine with the air filter
element removed. Doing so would allow
unfiltered air to enter, causing rapid en-
gine wear and possible engine damage. Additionally, the fuel injection system
would be affected, resulting in poor engine
performance and possible overheating.
Clean the primary air filter as follows.
1. Remove panel C (page 8-10).
2. Remove the air filter case cover by turn- ing the air filter case cover lock counter-
clockwise.TIPMake sure that the match mark on the cover
lock is aligned with the open match mark on
the air filter case cover.
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3. Remove the foam air filter.4. Remove the foam air filter element from
the air filter frame.1. Air filter case cover
2. Air filter case cover lock
3. Match mark
2 1
3
1. Foam air filter
1
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5. Wash the foam material gently but thor-oughly in parts cleaning solvent.
WARNING! Using gasoline or other flammable solvents to clean the air fil-
ter element can cause a fire or explo-
sion, which could lead to serious
injury.
[EWB03360]
6. Squeeze out the excess solvent. NOTICE: Do not twist the foam materi-
al when squeezing it.
[ECB02970]
7. Wash the foam material in warm soapy water to remove remaining solvent, then
rinse thoroughly with plain warm water.
8. Squeeze out the excess water. NOTICE:
Do not twist the foam material when
squeezing it.
[ECB02970]
9. Allow the foam air filter to dry thoroughly. Inspect for wear and tear and replace if
damaged or heavily worn.
1. Foam air filter element
2. Air filter frame
1
2
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