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PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6Installation
1. Measure the electrode gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
2. Clean the gasket surface. Wipe off
any grime from the threads.3. Install the spark plug and tighten it
to the specified torque.
NOTE:@ If a torque wrench is not available when
you are installing a spark plug, a good
estimate of the correct torque is 1/4 to
1/2 turn past finger tight. Have the
spark plug tightened to the specified
torque as soon as possible. @
EAU01703
Engine oilOil level inspection
1. Place the motorcycle on a level
place and hold it in an upright posi-
tion. Warm up the engine for seve-
ral minutes.NOTE:@ Be sure the motorcycle is positioned
straight up when checking the oil level.
A slight tilt toward the side can result in
false readings. @
a. Spark plug gapSpark plug gap:
0.8 ~ 0.9 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kg)
1. Oil level window
2. Maximum level mark
3. Minimum level mark
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6 2. Stop the engine and wait for a few
minutes. Check the oil level
through the level window located
at the lower part of the right side
crankcase cover.
NOTE:@ Wait a few minutes until the oil level
settles before checking. @3. The oil level should be between
the maximum and minimum
marks. If the level is low, fill the en-
gine with sufficient recommended
oil to reach the specified level.Engine oil and oil filter cartridge re-
placement
1. Warm up the engine for several
minutes.
2. Stop the engine. Place an oil pan
under the engine and remove the
oil filler cap.
3. Remove the drain bolt and drain
the oil.
4. Remove the oil filter by using an oil
filter wrench.
NOTE:@ An oil filter wrench is available at a
nearby Yamaha dealer. @
5. Reinstall the drain bolt and tighten
it to the specified torque.
6. Apply a light coat of engine oil to
the O-ring of new oil filter.NOTE:@ Make sure the O-ring is seated proper-
ly. @
1. Engine oil filler cap
1. Engine oil drain boltTightening torque:
Drain bolt:
43 Nm (4.3 m·kg)
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6-9
67. Install the new oil filter and tighten
it to the specified torque with an oil
filter wrench.
NOTE:@ When installing the oil filter, tighten it to
the proper torque by using a torque
wrench. @
8. Fill the engine with sufficient rec-
ommended oil. Install the oil filler
cap and tighten it.
EC000066
CAUTION:@ l
Do not put in any chemical addi-
tives. Engine oil also lubricates
the clutch and additives could
cause clutch slippage.
l
Be sure no foreign material en-
ters the crankcase.
@
9. Start the engine and warm it up for
several minutes. While warming
up, check for oil leakage. If oil
leakage is found, stop the engine
immediately and check for the
cause. NOTE:After the engine is started, the oil level
indicator light should go off if the oil is at
the specified level.
EC000067
CAUTION:@ If the indicator light flickers or re-
mains on, immediately stop the en-
gine and consult with a Yamaha
dealer. @
1. Oil filterTightening torque:
Oil filter:
17 Nm (1.7 m·kg)
Recommended oil:
See page 8-1.
Oil quantity:
Total amount:
4.3 L
Periodic oil change:
3.5 L
With oil filter replacement:
3.7 L
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6-10
6
EAU01220
Final gear oilCheck for oil leakage. If any leakage is
found, take the motorcycle to a
Yamaha dealer for repairs.
EAU01589
Coolant1. Remove the reservoir tank cover
by removing the screw.
2. Check the coolant level in the res-
ervoir tank when the engine is cold
as the coolant level will vary with
engine temperature. The coolant
level should be between the maxi-
mum and minimum marks.
3. If the level is low, remove the rid-
er’s seat, open the reservoir tank
cap and add coolant or distilled
water to raise it to the specified
level. (See page 3-10 for seat re-
moval procedures.)4. Install the reservoir tank cap and
rider’s seat.
5. Place the reservoir tank cover in
the original position and install the
screw.
EC000080
CAUTION:@ Hard water or salt water is harmful
to the engine. You may use distilled
water if you can’t get soft water. @
1. Final gear oil filler bolt
2. Final gear oil drain bolt
1. Reservoir tank
2. Maximum level mark
3. Minimum level markReservoir tank capacity:
0.84 L
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-11
6
NOTE:@ l
If water is added, have a Yamaha
dealer check the antifreeze con-
tent of the coolant as soon as pos-
sible.
l
Have a Yamaha dealer change
the coolant every two years.
l
The radiator fan operation is com-
pletely automatic. It is switched on
or off according to the coolant tem-
perature in the radiator.
@
EAU00630
Carburetor adjustmentThe carburetors are important parts of
the engine and require very sophisti-
cated adjustment. Most adjustments
should be left to a Yamaha dealer who
has the professional knowledge and
experience to do so. However, the idle
speed may be adjusted by the owner
as part of routine maintenance.
EC000095
CAUTION:@ The carburetors were set at the
Yamaha factory after many tests. If
they are changed, poor engine per-
formance and damage may result. @
EAU01168
Idle speed adjustmentNOTE:@ A diagnostic tachometer must be used
for this procedure. @1. Attach the tachometer. Start the
engine and warm it up for a few
minutes at approximately 1,000 to
2,000 r/min. Occasionally rev the
engine to 4,000 to 5,000 r/min.
The engine is warm when it quick-
ly responds to the throttle.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-22
6
EAU02985
Brake and clutch lever
lubricationLubricate the pivoting parts.
EAU02986
Sidestand lubricationLubricate the sidestand pivoting point
and metal-to-metal contact surfaces.
Check that the sidestand moves up
and down smoothly.
EW000113
WARNING
@ If the sidestand does not move
smoothly, consult a Yamaha dealer. @
Recommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-29
6
EAU02990*
Troubleshooting chart
EW000125
WARNING
@ Never check the fuel system while smoking or in the vicinity of an open flame. @
Check if there is fuel
in the fuel tank.1. Fuel
Enough fuel.
No fuel.
Go to compression check.
Supply fuel.
Engine doesn’t start, go to compression check.
Use the electric starter.2. Compression
There is compression.
No compression.
Go to ignition check.
Ask a Yamaha dealer to
inspect.
Remove spark
plugs and
check electrodes.3. Ignition
Wet.
Dry.
Wipe clean with dry cloth and correct
spark gap or replace spark plugs.
Ask a Yamaha dealer to inspect.
Engine doesn’t start, ask a Yamaha
dealer to inspect.Engine doesn’t start, go to battery
check.Open throttle half-way and start
the engine.
Use the electric starter.4. Battery
Engine turns over
quickly.
Engine turns over
slowly.
Battery good.Check connections or
recharge.
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6
5. Engine overheating
EW000070
WARNING
@ Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be blown
out under pressure, which could cause serious injury. Open the radiator cap as follows. Wait until the engine has
cooled. Remove the radiator cap stopper by removing the screw. Place a thick rag like a towel over the radiator cap
and slowly rotate the cap counterclockwise to the detent. This procedure allows any residual pressure to escape.
When the hissing sound has stopped, press down on the cap while turning counterclockwise and remove it. @NOTE:@ If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is changed to the recom-
mended coolant as soon as possible. @
Wait until the
engine has cooled.
Check the coolant level in the
reservoir tank and/or radiator.
Level is OK.Level is low, check the
cooling system for leakage.
No
leakage.Leakage.
Ask a Yamaha dealer to inspect
and repair the cooling system.Add coolant. (See NOTE.)
Restart the engine. If the engine overheats again, ask a
Yamaha dealer to inspect and repair the cooling system.
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