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9 8Use only the designated quali-
ty brake fluid. Otherwise, the
rubber seals may deteriorate,
causing leakage and poor
brake performance.
NOTE:
If DOT 4 is not available, DOT 3 can
be used.
8Refill with the same type of
brake fluid. Mixing fluids may
result in a harmful chemical
reaction and lead to poor
brake performance.
8Be careful that water does not
enter the master cylinder when
refilling. Water will significant-
ly lower the boiling point of
the fluid and may result in
vapor lock.8Brake fluid may deteriorate
painted surfaces or plastic
parts. Always clean up spilled
fluid immediately.
8Have a Yamaha dealer check
the cause if the brake fluid
level goes down.
EAU00742Brake fluid replacement
The brake fluid should be replaced
only by trained Yamaha service
personnel. Have the Yamaha deal-
er replace the following compo-
nents during periodic maintenance
or when they are damaged or leak-
ing:
8oil seals (every two years)
8brake hoses (every four years) Recommended brake fluid:
DOT 4
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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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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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EAU01495Front wheel installation
1. Install the speedometer gear
unit housing into the wheel
hub. Make sure the projections
are meshed into the slots.
2. Lift up the wheel between the
front fork legs. Make sure that
there is enough gap between
the brake pads before inserting
the brake disc and that the slot
in the speedometer gear unit
housing fits over the stopper
on the front fork outer tube.3. Install the wheel axle and axle
nut. Then, let the motorcycle
down.
4. Tighten the axle nut to the
specified torque.
5. Install the speedometer cable.EAU01496Rear 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. Loosen the wheel axle nut.
2. Remove the brake adjusting
nut and brake rod from the
brake cam lever.
1. Wheel axle nut
2. Chain adjusting plate
3. Brake adjusting nut
4. Brake rod
21
a
b
34
Tightening torque:
Axle nut:
90 Nm (9.0 m·kg)
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EAU01008Troubleshooting
Although Yamaha motorcycles
receive a rigid inspection before
shipment from the factory, trouble
may occur during operation.
Any problem in the fuel, compres-
sion, or ignition systems can cause
poor starting and loss of power.
The troubleshooting chart
describes a quick, easy procedure
for making checks.
If your motorcycle requires any
repair, bring it to a Yamaha dealer.
The skilled technicians at a
Yamaha dealership have the tools,
experience, and know-how to
properly service your motorcycle.
Use only genuine Yamaha parts on
your motorcycle. Imitation parts
may look like Yamaha parts, but
they are often inferior.
Consequently, they have a shorter
service life and can lead to expen-
sive repair bills.
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SPECIFICATIONS
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9
Specifications
Model TW125
Dimensions
Overall length 2,140 mm
Overall width 810 mm
Overall height 1,120 mm
Seat height 805 mm
Wheelbase 1,330 mm
Ground clearance 260 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and full
fuel tank)125 kg
Engine
Engine type Air-cooled 4-stroke, SOHC
Cylinder arrangement Forward inclined
single cylinder
Displacement 124 cm
3
Bore ´Stroke 57.0 ´48.8 mm
Compression ratio 10:1
Starting system Electric starter
Lubrication system Wet sumpEngine oil
Type
Recommended engine oil
classification API Service SE, SF, SG type
or higher
cC
Be sure to use motor oils that do not contain anti-friction
modifiers. Passenger car motor oils (often labeled “Energy
Conserving”) contain anti-friction additives which will cause
clutch and/or starter clutch slippage, resulting in reduced
component life and poor engine performance.
Capacity
Periodic oil change 1.0 L
With oil filter replacement 1.1 L
Total amount 1.3 L
Air filterWet type element
–10° 0° 10° 20° 30°
40°
SAE 10W/30
SAE 10W/40
SAE 20W/40
SAE 20W/50
–20°
SAE 15W/40 50°C
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