light YAMAHA TW125 2003 User Guide

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.
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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
EAU04577
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.
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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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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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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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w
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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6-26
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04369
To adjust the drive chain slack
1. Loosen the brake pedal free play
adjusting nut.
2. Loosen the axle nut.
3. To tighten the drive chain, turn
the adjusting plate on each side
of the swingarm in direction a.
To loosen the drive chain, turn
the adjusting plate on each side
of the swingarm in direction b,
and then push the rear wheel for-
ward.
32
a
b
1
1. Brake pedal free play adjusting nut
2. Axle nut
3. Drive chain adjusting plate
NOTE:
Make sure that both adjusting plates
are in the same position for proper
wheel alignment.
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Improper drive chain slack will
overload the engine as well as
other vital parts of the motorcycle
and can lead to chain slippage or
breakage. To prevent this from
occurring, keep the drive chain
slack within the specified limits.
4. Tighten the axle nut to the speci-
fied torque.5. Adjust the brake pedal free play.
(See page 6-21 for brake pedal
free play adjustment proce-
dures.)
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w
After adjusting the brake pedal
free play, check the operation of
the brake light.
Tightening torque:
Axle nut:
90 Nm (9.0 m·kgf)
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6-34
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Do not use a fuse of a higher
amperage rating than recommend-
ed to avoid causing extensive
damage to the electrical system
and possibly a fire.
3. Turn the key to “ON” and turn on
the electrical circuits to check if
the devices operate.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
EAU04189
Replacing the headlight bulb
This motorcycle is equipped with a
quartz bulb headlight. If the headlight
bulb burns out, replace it as follows.
1. Remove the headlight unit by
removing the screws.
1
1. Screw (×2)
2. Disconnect the headlight cou-
pler, and then remove the bulb
cover.
1
2
1. Headlight coupler
2. Bulb cover
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6-35
PERIODIC MAINTENANCE AND MINOR REPAIR
63. Unhook the headlight bulb hold-
er, and then remove the defec-
tive bulb.EW000119
w
Headlight bulbs get very hot.
Therefore, keep flammable prod-
ucts away from a lit headlight bulb,
and do not touch the bulb until it
has cooled down.
4. Place a new headlight bulb into
position, and then secure it with
the bulb holder.
1
1. Headlight bulb holder
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Do not touch the glass part of the
headlight bulb to keep it free from
oil, otherwise the transparency of
the glass, the luminosity of the
bulb, and the bulb life will be
adversely affected. Thoroughly
clean off any dirt and fingerprints
on the headlight bulb using a cloth
moistened with alcohol or thinner.
a
a. Do not touch the glass part of the bulb.
5. Install the headlight bulb cover,
and then connect the coupler.
6. Install the headlight unit by
installing the screws.
7. Have a Yamaha dealer adjust
the headlight beam if necessary.
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6-36
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU03497
Replacing a turn signal light
bulb
1. Remove the turn signal light lens
by removing the screw.
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
screw.
1
2
3
1. Screw
2. Lens
3. Bulb
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Do not overtighten the screw, oth-
erwise the lens may break.
EAU01623
Replacing the tail/brake light
bulb
1. Remove the tail/brake light lens
by removing the screws.
1
1. Screw (×2)
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