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7. Install the oil filler bolt and its gasket, andthen tighten the bolt to the specified
torque.
8. Check for oil leakage. If oil leakage is found, check for the cause.EBU36064Differential gear oilCheck the oil level and change the differential
gear oil at the intervals specified in the period-
ic maintenance chart.NOTICEECB03600When checking or changing the differen-
tial gear oil, make sure that no foreign ma-
terial enters the differential gear case. If
necessary, clean the differential gear oil
filler bolt and surrounding area.
TIPIf the recommended gear oil is not available,
SAE 80W-90 API GL-4 or GL-5 hypoid gear
oil may be used instead. Checking the differential gear oil level 1. Park the vehicle on a level surface.
2. Remove the differential gear oil filler bolt and its gasket, and then check the oil lev-
el. It should be up to the brim of the filler
hole.
Tightening torque:Final gear oil filler bolt:22 N·m (2.2 kgf·m, 16 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)
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3. If the level is low, add sufficient oil of therecommended type to raise it to the
specified level.
4. Check the gasket for damage, and re- place it if necessary.
5. Install the differential gear oil filler bolt
and its gasket, and then tighten the bolt
to the specified torque. Changing the differential gear oil
1. Park the vehicle 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.1. Differential gear oil filler bolt
2. Gasket
3. Differential gear oil
4. Correct oil level
1
2
3
4
Tightening torque:Differential gear oil filler bolt:23 N·m (2.3 kgf·m, 17 lb·ft)1. Differential gear oil drain bolt
2. Gasket
1 2
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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.
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.
EBU35112CoolantThe coolant level should be checked regular-
ly. In addition, the coolant must be changed
at the intervals specified in the periodic main-
tenance chart.TIPIf genuine Yamaha coolant is not available,
use an ethylene glycol antifreeze containing
corrosion inhibitors for aluminum engines and
mix with distilled water at a 1:1 ratio.
Tightening torque:Differential gear oil drain bolt:9.8 N·m (0.98 kgf·m, 7.2 lb·ft)
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):0.56 L (0.59 US qt, 0.49 Imp.qt)
Radiator (including all routes): 3.78 L (4.00 US qt, 3.33 Imp.qt)
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NOTICEECB02190Mix antifreeze with distilled water only.
However, if distilled water is not available,
soft water may be used for refilling. Do not
use hard water or salt water since they are
harmful to the engine. To check the coolant level1. Park the vehicle on a level surface.
2. Wait for the engine to cool for an accurate reading.
3. Look at the coolant level in the coolant reservoir. 4. If the coolant is at or below the minimum
level mark, remove panel C. (See page
9-11.)
5. Remove the coolant reservoir cap, add coolant up to the maximum level mark,
and then install the cap. 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
1. Maximum level mark
2. Minimum level mark
21
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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]
6. Install the panel when finished servicing
the vehicle. To change the coolant
The coolant must be changed at the intervals
specified in the periodic maintenance chart.
Have a Yamaha dealer change the coolant.
WARNING! Never attempt to remove the
radiator cap when the engine is hot.
[EWB04250]
EBU32400
Axle bootsCheck the axle boots for holes or tears.
If any damage is found, have them replaced
by a Yamaha dealer.
1. Coolant reservoir cap
1
1. Front axle boot
1
1
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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. 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.1. Rear axle boot
1
1
Specified spark plug:
NGK/CR9EB
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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 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.
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, 9.6 lb·ft)
1
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EBU38320Air 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).
TIPService the air filters more frequently when
operating in wet or dusty 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.
1. Primary air filter
2. Secondary air filter
1
2
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