2003 YAMAHA TW125 light

4-2
PRE-OPERATION CHECKS
4
Throttle grip•Make sure that operation is smooth.
•Check cable free play.
•If necessary, have Yamaha dealer adjust cable free play and lubricate cable and
grip housing.6-15, 6-28
Control cables•Make sure that operation is smooth.
•Lubricate if necessary.6-27
Drive chain•Check chain slack.
•Adjust if necessary.
•Check chain condition.
•Lubricate if necessary.6-25–6-27
Wheels and tires•Check for damage.
•Check tire condition and tread depth.
•Check air pressure.
•Correct if necessary.6-16–6-19
Brake and shift pedals•Make sure that operation is smooth.
•Lubricate pedal pivoting points if necessary.6-28
Brake and clutch levers•Make sure that operation is smooth.
•Lubricate lever pivoting points if necessary.6-29
Sidestand•Make sure that operation is smooth.
•Lubricate pivot if necessary.6-29
Chassis fasteners•Make sure that all nuts, bolts and screws are properly tightened.
•Tighten if necessary.—
Instruments, lights, signals
and switches•Check operation.
•Correct if necessary.3-1–3-4, 6-34–6-37
Sidestand switch•Check operation of ignition circuit cut-off system.
•If system is defective, have Yamaha dealer check vehicle.3-12–3-13 ITEM CHECKS PAGE
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5-1
EAU00372
OPERATION AND IMPORTANT RIDING POINTS
5
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8Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer
regarding any control or func-
tion that you do not thorough-
ly understand.
8Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
8Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.
EAU04692
Starting a cold engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
8The transmission is in the neutral
position.
8The transmission is in gear with
the clutch lever pulled and the
sidestand up.
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8Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-13.
8Never ride with the sidestand
down.
1. Turn the fuel cock lever to “ON”.
2. Turn the key to “ON” and make
sure that the engine stop switch
is set to “#”.
3. Shift the transmission into the
neutral position.
NOTE:
When the transmission is in the neu-
tral position, the neutral indicator light
should be on, otherwise have a
Yamaha dealer check the electrical
circuit.
ONFUEL
RES
OFF
1ON
1. Arrow mark positioned over “ON”
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5-3
OPERATION AND IMPORTANT RIDING POINTS
5
EAU00423
Shifting
Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing
hills, etc.
The gear positions are shown in the
illustration.
NOTE:
To shift the transmission into the neu-
tral position, press the shift pedal
down repeatedly until it reaches the
end of its travel, and then slightly
raise it.
EC000048
cC
8Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long
distances. The transmission is
properly lubricated only when
the engine is running.
Inadequate lubrication may
damage the transmission.
8Always use the clutch while
changing gears to avoid dam-
aging the engine, transmis-
sion, and drive train, which are
not designed to withstand the
shock of forced shifting.
EAU02941
Recommended shift points
(for Switzerland only)
The recommended shift points during
acceleration are shown in the table
below.
NOTE:
When shifting down two gears at a
time, reduce the speed accordingly
(e.g., down to 35 km/h when shifting
from 4th to 2nd gear).
1
N5
4
3
2
1
1. Shift pedal
N. Neutral position
Shift point
(km/h)
1st→2nd
2nd→3rd
3rd→4th
4th→5th23
36
50
60
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5-4
OPERATION AND IMPORTANT RIDING POINTS
5
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Tips for reducing fuel
consumption
Fuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Turn the starter (choke) off as
soon as possible.
8Shift up swiftly, and avoid high
engine speeds during accelera-
tion.
8Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the
engine.
8Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad cross-
ings).
EAU00436
Engine break-in
There is never a more important peri-
od in the life of your engine than the
period between 0 and 1,000 km. For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do
not put an excessive load on it for the
first 1,000 km. The various parts in
the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheat-
ing must be avoided.
EAU04398
0–500 km
Avoid prolonged operation above 1/3
throttle.
500–1,000 km
Avoid prolonged operation above 1/2
throttle.
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cC
After 1,000 km of operation, the
engine oil must be changed, and
the oil filter element and the oil
strainer cleaned.
1,000 km and beyond
The vehicle can now be operated
normally.
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cC
If any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealer
check the vehicle.
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6-4
PERIODIC MAINTENANCE AND MINOR REPAIR
6EAU03541
NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake service
9Regularly check and, if necessary, correct the brake fluid level.
9Every two years replace the internal components of the brake master cylinder and caliper, and change the brake
fluid.
9Replace the brake hoses every four years and if cracked or damaged.
21*Carburetor•Check starter (choke) operation.
•Adjust engine idling speed.√√√√√ √
22 Engine oil•Change.
•Check oil level and vehicle for oil leakage.√√√√√ √
23 Engine oil filter element•Clean.√√√
24
*Engine oil strainer•Clean.√
25
*Front and rear brake
switches•Check operation.√√√√√ √
26 Moving parts and cables•Lubricate.√√√√ √
27
*Throttle grip housing
and cable•Check operation and free play.
•Adjust the throttle cable free play if necessary.
•Lubricate the throttle grip housing and cable.√√√√ √
28
*Lights, signals and
switches•Check operation.
•Adjust headlight beam.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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6-8
PERIODIC MAINTENANCE AND MINOR REPAIR
6 To check the spark plug
1. Check that the porcelain insula-
tor around the center electrode
of the spark plug is a medium-to-
light tan (the ideal color when the
motorcycle is ridden normally).
NOTE:
If the spark plug shows a distinctly
different color, the engine could be
defective. Do not attempt to diagnose
such problems yourself. Instead,
have a Yamaha dealer check the
motorcycle.
2. Check the spark plug for elec-
trode erosion and excessive car-
bon or other deposits, and
replace it if necessary.To install the spark plug
1. Measure the spark plug gap with
a wire thickness gauge and, if
necessary, adjust the gap to
specification.
2. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then
tighten it to the specified torque.
a
a. Spark plug gap
NOTE:
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is
1/4–1/2 turn past finger tight.
However, the spark plug should be
tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
Spark plug gap:
0.6–0.7 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf)
Specified spark plug:
DR8EA (NGK)
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6-9
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04616
Engine oil and oil filter
element
The engine oil level should be
checked before each ride. In addition,
the oil must be changed and the oil
filter element cleaned at the intervals
specified in the periodic maintenance
and lubrication chart.
To check the engine oil level
1. Place the motorcycle on a level
surface and hold it in an upright
position.
NOTE:
Make sure that the motorcycle is
positioned straight up when checking
the oil level. A slight tilt to the side
can result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.3. Wait a few minutes until the oil
settles, and then check the oil
level through the check window
located at the bottom-right side
of the crankcase.
NOTE:
The engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is below the min-
imum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
2
3 1
1. Engine oil level check window
2. Maximum level mark
3. Minimum level mark
To change the engine oil (with or
without oil filter element cleaning)
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the
engine to collect the used oil.
3. Remove the engine oil filler cap
and drain bolt to drain the oil
from the crankcase.
1
1. Engine oil filler cap
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6-22
PERIODIC MAINTENANCE AND MINOR REPAIR
6 To increase the brake pedal free
play, turn the adjusting nut at the
brake rod in direction a. To
decrease the brake pedal free play,
turn the adjusting nut in direction b.
b
a1
1. Brake pedal free play adjusting nut
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8After adjusting the drive chain
slack or removing and
installing the rear wheel,
always check the brake pedal
free play.
8If proper adjustment cannot be
obtained as described, have a
Yamaha dealer make this
adjustment.
8After adjusting the brake pedal
free play, check the operation
of the brake light.
EAU00713
Adjusting the rear brake light
switch
The rear brake light switch, which is
activated by the brake pedal, is prop-
erly adjusted when the brake light
comes on just before braking takes
effect. If necessary, adjust the brake
light switch as follows.
Turn the adjusting nut while holding
the rear brake light switch in place.
To make the brake light come on ear-
lier, turn the adjusting nut in direction
a. To make the brake light come on
later, turn the adjusting nut in direc-
tion b.
1
2
a
b
1. Rear brake light switch
2. Adjusting nut
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