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EAU00634Throttle cable free play
adjustment
NOTE:
Before checking the throttle cable
free play, the engine idling speed
should be adjusted.
Adjust the throttle cable by turning
the adjusting nut so that specified
free play at the throttle grip is
obtained.
1. Adjusting nut
2. Locknut
c. Free play
1. Loosen the locknut.
2. Turn the adjusting nut in direc-
tion ato increase free play
and in direction bto decrease
free play.
3. Tighten the locknut.
EAU00637Valve clearance adjustment
The correct valve clearance
changes with use, resulting in
improper fuel/air supply or engine
noise. To prevent this, the valve
clearance must be adjusted regu-
larly. This adjustment however,
should be left to a professional
Yamaha service technician.
1
2a
bc
Free play:
3 ~ 5 mm
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EC000096
cC
Too little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits.
4. Tighten the wheel axle nut to
the specified torque.
5. Adjust the brake pedal free
play.
EW000103
w
Check the operation of the brake
light after adjusting the rear brake.
EAU01106*Drive chain lubrication
The 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 regular-
ly. This service is especially neces-
sary when riding in dusty areas.
The drive chain should be lubri-
cated every 500 km. First, remove
all dirt and mud from the chain
with a brush or cloth. Then, spray
any of the many brands of spray-
type chain lubricant between
both rows of side plates and on
all center rollers.
To clean the chain thoroughly,
remove it from the motorcycle,
dip it in solvent, and clean out as
much dirt as possible. Then, take
the chain out of the solvent to
dry it, and immediately lubricate
it to prevent it from rusting.
EC000097
cC
Be sure to oil the chain after wash-
ing the motorcycle or riding in the
rain.
Tightening torque:
Wheel axle nut:
90 Nm (9.0 m·kg)
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EAU02962Cable inspection and
lubrication
EW000112
w
Damage to the outer housing of
cables may lead to internal rusting
and interfere with the cable move-
ment. Replace damaged cables as
soon as possible to prevent unsafe
conditions.
Lubricate the cables and cable
ends. If a cable does not operate
smoothly, ask a Yamaha dealer to
replace it.EAU00773Throttle cable and grip
lubrication
The throttle twist grip assembly
should be greased at the time that
the cable is lubricated, since the
grip must be removed 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. Recommended lubricant:
Engine oil
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EAU02984Brake and shift pedal
lubrication
Lubricate the pivoting parts.
EAU02985Brake and clutch lever
lubrication
Lubricate the pivoting parts.
EAU02986Sidestand lubrication
Lubricate the sidestand pivoting
point and metal-to-metal contact
surfaces. Check that the sidestand
moves up and down smoothly.
EW000113
w
If the sidestand does not move
smoothly, consult a Yamaha deal-
er.
Recommended lubricant:
Engine oilRecommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
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EAU00794Steering inspection
Periodically inspect the condition
of the steering. Worn out or loose
steering bearings may be danger-
ous. Place a stand under the
engine to raise the front wheel off
the ground. Hold the lower end of
the front forks and try to move
them forward and backward. If any
free play can be felt, ask a Yamaha
dealer to inspect and adjust the
steering. Inspection is easier if the
front wheel is removed.
EW000115
w
Securely support the motorcycle
so there is no danger of it falling
over.
EAU01144Wheel bearings
If there is play in the front or rear
wheel hub or if the wheel does not
turn smoothly, have a Yamaha
dealer inspect the wheel bearings.
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92. Push the bulb inward and turn
it counterclockwise.
1. Screw (´2)
3. Place a new bulb in the socket.
Push the bulb inward and turn
it clockwise until it engages
into the socket.
4. Install the lens and the screws.
EC000108
cC
Do not over-tighten the screws as
the lens may break.
1. Bulb
EAU01579Supporting the motorcycle
Since the Yamaha TW125 has no
centerstand, follow these precau-
tions when removing the front and
rear wheel or performing other
maintenance requiring the motor-
cycle to stand upright. Check that
the motorcycle is in a stable and
level position before starting any
maintenance. A strong wooden
box can be placed under the
engine for added stability.
Front wheel service
To stabilize the rear of the motor-
cycle, either use a motorcycle
stand or place a motorcycle jack
under the frame in front of the rear
wheel to prevent it from moving
from side to side. Then use a
motorcycle stand to elevate the
front wheel off of the ground.11
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9 Rear wheel service
Use a motorcycle stand or motor-
cycle jack to elevate the motorcycle
so the rear wheel is off the ground.
Alternatively, two jacks can be
placed under the frame or
swingarm.
1
2
EAU01494Front wheel removalEW000122
w
8It is advisable to have a
Yamaha dealer service the
wheel.
8Securely support the motorcy-
cle so there is no danger of it
falling over.
1. Remove the speedometer
cable from the front wheel
side.
1. Speedometer cable
2. Wheel axle nut
2. Loosen the wheel axle nut.
3. Elevate the front wheel by
placing a suitable stand under
the engine.
4. Remove the wheel axle nut,
the wheel axle and the front
wheel. Make sure the motorcy-
cle is properly supported.
NOTE:
Do not depress the brake lever
when the disc and caliper are sepa-
rated.
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6-39
EAU03009Troubleshooting chartEW000125
w
Never check the fuel system while smoking or in the vicinity of an open flame.
1. Fuel
2. Compression
3. Ignition
4. Battery
Use the electric starter.
Remove spark
There is compression.
Go to ignition check.
No compression.
Ask a Yamaha dealer to inspect.
Wet.
Dry.Wipe clean with dry cloth and Open throttle half-way and start
Ask a Yamaha dealer to inspect.
Engine turns over
Engine turns overBattery good.
Check fluid, recharge,
Use the electric starter.
Check if there is fuel
Enough fuel.
No fuel.Go to compression check.
Supply fuel.
in the fuel tank.
electrodes. plug and check
quickly.
slowly. check connections.Engine doesn’t start, go to battery
check.the engine. correct spark gap or replace plug.
Engine doesn’t start, ask a Yamahadealer to inspect.
Engine doesn’t start, go to compression check.
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