2002 YAMAHA DT125R maintenance

6-38
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EC000108
cCDo not overtighten the screws,
otherwise the lens may break.
EAU01623
Replacing the tail/brake light
bulb1. Remove the tail/brake light lens
by removing the screws.
2. Remove the defective bulb by
pushing it in and turning it coun-
terclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screws.
1
2
3
1. Screw (×2)
2. Lens
3. Bulb
ECA00065
cCDo not overtighten the screw, oth-
erwise the lens may break.
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6-39
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00898
Front wheelTo remove the front wheel
EW000122
w8It is advisable to have a
Yamaha dealer service the
wheel.
8Securely support the motorcy-
cle so that there is no danger
of it falling over.1. Remove the brake disc cover by
removing the screws.
122
1. Disc cover
2. Screw (×2)
To service the rear wheel
Raise the rear wheel off the ground
by using a motorcycle stand or, if a
motorcycle stand is not available, by
placing a jack either under each side
of the frame in front of the rear wheel
or under each side of the swingarm.
EAU01579
Supporting the motorcycleSince this model is not equipped with
a centerstand, follow these precau-
tions when removing the front and
rear wheel or performing other main-
tenance requiring the motorcycle to
stand upright. Check that the motor-
cycle is in a stable and level position
before starting any maintenance. A
strong wooden box can be placed
under the engine for added stability.
To service the front wheel
1. Stabilize the rear of the motorcy-
cle by using a motorcycle stand
or, if an additional motorcycle
stand is not available, by placing
a jack under the frame in front of
the rear wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
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6-40
PERIODIC MAINTENANCE AND MINOR REPAIR
6
ECA00048
cCDo not apply the brake after the
wheel has been removed together
with the brake disc, otherwise the
brake pads will be forced shut.
2. Disconnect the speedometer
cable from the front wheel.
3. Lift the front wheel off the ground
according to the procedure on
page 6-39.
4. Loosen the wheel axle holder
nuts.
5. Pull the wheel axle out, and then
remove the wheel.
3
2 1
1. Speedometer cable
2. Axle holder nut (×4)
3. Wheel axle
EAU03555
To install the front wheel
1. Install the speedometer gear unit
into the wheel hub so that the
projections mesh with the slots.
2. Lift the wheel up between the
fork legs.
1
1. Speedometer gear unit
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6-41
PERIODIC MAINTENANCE AND MINOR REPAIR
67. After tightening the holder nuts,
while applying the front brake,
push down on the handlebars
several times to check if the front
fork compress and rebounds
smoothly.
8. Connect the speedometer cable.
6. Tighten the axle holder nuts to
the specified tightening torque.
Tighten the upper nuts first and
then lower ones. When tightened
in this sequence, there should be
a gap formed at the bottom of
the axle holder.
NOTE:
Make sure that there is enough
space between the brake pads
before inserting the brake disc and
that the slot in the speedometer gear
unit fits over the retainer on the fork
leg.3. Install the wheel axle.
4. Lower the front wheel so that it is
on the ground.
5. Tighten the wheel axle to the
specified torque.
1
1. Retainer
Tightening torque:
Wheel axle:
58 Nm (5.8 m0kgf)Tightening torque:
Axle holder nut:
10 Nm (1.0 m0kgf)
a
a. Gap
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6-42
PERIODIC MAINTENANCE AND MINOR REPAIR
6
ECA00048
cCDo not apply the brake after the
wheel has been removed together
with the brake disc, otherwise the
brake pads will be forced shut.
EAU04237
Rear wheelWheel (rear)
EW000122
w8It is advisable to have a
Yamaha dealer service the
wheel.
8Securely support the motorcy-
cle so that there is no danger
of it falling over.1. Loosen the axle nut.
2. Lift the rear wheel off the ground
according to the procedure on
page 6-39.
3. Remove the swingarm end bolts.
2
2
1
1. Axle nut
2. Swingarm end bolt (×2)
4. Turn the drive chain adjusting
plate on each side of the
swingarm fully in direction a.
5. Push the wheel forward, and
then remove the drive chain from
the rear sprocket.NOTE:
The drive chain does not need to be
disassembled in order to remove and
install the rear wheel.6. Pull the wheel axle out from the
left-hand side, and then remove
the wheel by pulling it back.
1
a
1. Chain adjusting plate
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6-43
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU03087
TroubleshootingAlthough Yamaha motorcycles
receive a thorough inspection before
shipment from the factory, trouble
may occur during operation. Any
problem in the fuel, compression, or
ignition systems, for example, can
cause poor starting and loss of
power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcy-
cle require any repair, take it to a
Yamaha dealer, whose skilled techni-
cians have the necessary tools,
experience, and know-how to service
the motorcycle properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life
and can lead to expensive repair
bills.
EAU01806
To install the rear wheel
1. Install the drive chain onto the
rear sprocket, and then insert the
wheel axle from the left side.NOTE:
Make sure that there is enough
space between the brake pads
before inserting the brake disc
between the pads.2. Install the swingarm end bolts,
and then lower the rear wheel so
that it is on the ground.
3. Adjust the drive chain slack.
(See page 6-27 for drive chain
slack adjustment procedures.)
4. Tighten the axle nut and
swingarm end bolts to the speci-
fied torques.
Tightening torques:
Axle nut:
90 Nm (9.0 m0kgf)
Swingarm end bolts:
3 Nm (0.3 m0kgf)
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6-44
PERIODIC MAINTENANCE AND MINOR REPAIR
6
Check if there is fuel1. Fuel
Enough fuel.
No fuel.
Go to compression check.
Supply fuel.
Engine doesn’t start, go to compression check.
Use kickstarter.2. Compression
There is compression.
No compression.
Go to ignition check.
Ask a Yamaha dealer to
Remove spark plug3. Ignition
Wet.
Dry.
Wipe clean with dry cloth and correct
Ask a Yamaha dealer to inspect.
Engine doesn’t start, ask a YamahaOpen throttle half-way and start
in the fuel tank.
and check electrodes.spark gap or replace spark plug. the engine.
dealer to inspect. inspect.
EAU03108
Troubleshooting charts
EW000125
wKeep away open flames and do not smoke while checking or working on the fuel system.
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6-45
PERIODIC MAINTENANCE AND MINOR REPAIR
6
Wait until the
Check the coolant level in the
Level is OK.Level is low, check the
NoLeakage.
Ask a Yamaha dealer to inspectAdd coolant. (See NOTE.)
Restart the engine. If the engine overheats again, ask a
engine has cooled.reservoir tank and/or radiator.cooling system for leakage.
Yamaha dealer to inspect and repair the cooling system.leakage.
and repair the cooling system.
4. Engine overheating
EW000070
w8Do 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. Be sure to wait until the engine has cooled.
8After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the
hissing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the
cap.NOTE:
If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is changed to the rec-
ommended coolant as soon as possible.
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