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6-10
6 8. Start the engine and warm up for a
few minutes. While warming up,
check for oil leakage. If oil leakage
is found, stop the engine immedi-
ately and check for the cause.
9. Stop the engine and check the oil
level.
EAU03024*
Cooling system1. Check the coolant level in the
coolant reservoir when the engine
is cold as the coolant level will vary
with engine temperature. The
coolant level should be between
the maximum and minimum
marks.
2. If the level is low, remove the seat.
(See page 3-12 for seat removal
and installation procedures.)
3. Remove the coolant reservoir cap,
then add coolant or distilled water
to raise it to the specified level.4. Install the coolant reservoir cap
and seat.
ECA00041
CAUTION:@ Hard water or salt water is harmful
to the engine. You may use soft wa-
ter if you can’t get distilled water. @
1. Coolant reservoir
2. Maximum level mark
3. Minimum level mark
1. Coolant reservoir capCoolant reservoir capacity:
0.3 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
The radiator fan operation is com-
pletely automatic. It is switched on
or off according to the coolant tem-
perature in the radiator.
@5. If your motorcycle overheats, see
page 6-34 for details.
EAU01176*
Changing the coolant1. Put the motorcycle on a level
place.
2. Remove cowling B. (See page 6-5
for cowling removal and installa-
tion procedures.)
3. Place a container under the en-
gine.
4. Remove the radiator cap stopper
bolt and radiator cap.
EW000067
WARNING
@ Do not remove the radiator cap
when the engine is hot. @
5. Remove the water pump drain bolt
and cylinder drain bolt.
1. Radiator cap stopper bolt
2. Radiator cap
1. Water pump drain bolt
2. Cylinder drain bolt
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
6 6. Remove the seat. (See page 3-12
for seat removal and installation
procedures.)
7. Remove the coolant reservoir by
removing the bolts.
8. Remove the coolant reservoir
hose clamp and disconnect the
hose.
9. Drain the coolant from the coolant
reservoir by turning it upside
down.
10. Install the hose and connect the
coolant reservoir hose clamp. 11. Drain the coolant completely and
thoroughly flush the cooling sys-
tem with clean tap water.
12. If the washers are damaged, re-
place them. Tighten the water
pump drain bolt and cylinder drain
bolt to the specified torques.
13. Pour the recommended coolant
into the radiator until it is full.
ECA00041
CAUTION:@ Hard water or salt water is harmful
to the engine. You may use soft wa-
ter if you can’t get distilled water. @14. Run the engine several minutes.
Stop the engine and recheck the
coolant level in the radiator. If it is
low, add more coolant until it
reaches the top of the radiator.
15. Fill the coolant reservoir with cool-
ant up to maximum level.
16. Install the radiator cap, radiator
cap stopper bolt and coolant res-
ervoir cap.
17. Check for coolant leakage. If any
leakage is found, ask a Yamaha
dealer to inspect the cooling sys-
tem.
1. Coolant reservoir
2. Bolt
3. Coolant reservoir hose clamp
4. Hose
Tightening torque:
Water pump and cylinder drain
bolts:
10 Nm (1.0 m·kg)
Recommended antifreeze:
High quality ethylene glycol
antifreeze containing corrosion
inhibitors for aluminum engines.
Antifreeze and water mixing ratio:
1 : 1
Total amount:
1.7 L
Coolant reservoir capacity:
0.3 L
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6
EC000082
CAUTION:@ l
Make sure the air filter is prop-
erly seated in the air filter case.
l
The engine should never be run
without the air filter installed.
Excessive piston and/or cylin-
der wear may result.
@
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. @
EAU00632
Idle speed adjustment1. 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 quickly responds to the
throttle.
2. Set the idle to the specified engine
speed by adjusting the throttle
stop screw. Turn the screw in di-
rection
a to increase engine
speed and in direction
b to de-
crease engine speed.1. Throttle stop screw
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6
NOTE:@ If the specified idle speed cannot be
obtained by performing the above ad-
justment, consult a Yamaha dealer. @
EAU00635
Throttle cable free play
inspectionThere should be a free play of 3 ~
5 mm at the throttle grip. If the free play
is incorrect, ask a Yamaha dealer to
make this adjustment.
EAU00637
Valve clearance adjustmentThe correct valve clearance changes
with use, resulting in improper fuel/air
supply or engine noise. To prevent this,
the valve clearance must be adjusted
regularly. This adjustment however,
should be left to a professional
Yamaha service technician. Standard idle speed:
1,050 ~ 1,250 r/min
a. Free play
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6
EC000096
CAUTION:@ Too little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits. @3. After adjusting, tighten the axle nut
and caliper bracket bolt to the
specified torque.
EAU03006
Drive chain lubricationThe chain consists of many parts which
work with each other. If the chain is not
maintained properly, it will wear out
quickly. Therefore, the chain must be
serviced regularly. This service is es-
pecially necessary when riding in dusty
areas. This motorcycle is equipped
with a sealed type chain. Steam clean-
ing, high-pressure washers, and sol-
vents can damage the drive chain, so
do not use these for cleaning it. Use
only kerosene to clean the drive chain.
Wipe it dry, and thoroughly lubricate it
with SAE 30 ~ 50W motor oil. Do not
use any other lubricants on the drive
chain. They may contain solvents that
could damage the sealed chain.
EC000097
CAUTION:@ Be sure to oil the chain after wash-
ing the motorcycle or riding in the
rain. @
EAU02962
Cable inspection and
lubrication
EW000112
WARNING
@ Damage to the outer housing of ca-
bles may lead to internal rusting and
interfere with the cable movement.
Replace damaged cables as soon as
possible to prevent unsafe condi-
tions. @Lubricate the cables and cable ends. If
a cable does not operate smoothly, ask
a Yamaha dealer to replace it.
1. Caliper bracket bolt
Tightening torque:
Axle nut:
110 Nm (11.0 m·kg)
Caliper bracket bolt:
35 Nm (3.5 m·kg)
Recommended lubricant:
Engine oil
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6
EAU00773
Throttle cable and grip
lubricationThe throttle twist grip assembly should
be greased at the time that the cable is
lubricated, since the grip must be re-
moved to get at the end of the throttle
cable. After removing the screws, hold
the end of the cable up in the air and
put in several drops of lubricant. With
the throttle grip disassembled, coat the
metal surface of the grip assembly with
a suitable all-purpose grease.
EAU02984
Brake and shift pedal
lubricationLubricate the pivoting parts.
EAU02985
Brake and clutch lever
lubricationLubricate the pivoting parts.
Recommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
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6
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. @
EAU00790
Rear suspension lubricationLubricate the pivoting parts.
Recommended lubricant:
Engine oilRecommended lubricant:
Molybdenum disulfide grease
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