light YAMAHA TW125 2004 User Guide

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OPERATION AND IMPORTANT RIDING POINTS
EAU15950
WARNING

EWA10270

Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer re-
garding any control or function
that you do not thoroughly un-
derstand.

Never 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.

Before 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.
EAU16060
Starting a cold engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:

The transmission is in the neutral
position.

The transmission is in gear with
the clutch lever pulled and the sid-
estand up.
WARNING

EWA10290

Before starting the engine,
check the function of the igni-
tion circuit cut-off system ac-
cording to the procedure
described on page 3-11.

Never 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 neu-
tral position.
NOTE:

When the transmission is in the neutral
position, the neutral indicator light
should be on, otherwise have a
Yamaha dealer check the electrical cir-
cuit.
4. Turn the starter (choke) on and
completely close the throttle. (See
page 3-8.)
5. Start the engine by pushing the
start switch.
NOTE:

If the engine fails to start, release the
start switch, wait a few seconds, and
then try again. Each starting attempt
should be as short as possible to pre-
serve the battery. Do not crank the en-
gine more than 10 seconds on any one
attempt.
6. After starting the engine, move the
starter (choke) back halfway.
CAUTION:

ECA11040
For maximum engine life, never ac-
celerate hard when the engine is

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OPERATION AND IMPORTANT RIDING POINTS
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cold!
7. When the engine is warm, turn the
starter (choke) off.
NOTE:

The engine is warm when it responds
normally to the throttle with the starter
(choke) turned off.
EAU16640
Starting a warm engine
Follow the same procedure as for start-
ing a cold engine with the exception
that the starter (choke) is not required
when the engine is warm.
EAU16671
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 il-
lustration.
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.
1. Shift pedal
2. Neutral position
1
N5
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2
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2

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CAUTION:

ECA10260

Even 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 dis-
tances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.

Always use the clutch while
changing gears to avoid damag-
ing the engine, transmission,
and drive train, which are not
designed to withstand the
shock of forced shifting.
EAU32810
Recommended shift points (for
Switzerland only)
The recommended shift points during
acceleration are shown in the table be-
low.
NOTE:

When shifting down two gears at a
time, reduce the speed accordingly
[e.g., down to 35 km/h (22 mi/h) when
shifting from 4th to 2nd gear].
EAU16800
Tips for reducing fuel
consumption
Fuel consumption depends largely on
your riding style. Consider the following
tips to reduce fuel consumption:

Turn the starter (choke) off as
soon as possible.

Shift up swiftly, and avoid high en-
gine speeds during acceleration.

Do not rev the engine while shifting
down, and avoid high engine
speeds with no load on the engine.

Turn 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 crossings).
Shift up points:
1st
→
2nd: 23 km/h (14 mi/h)
2nd
→
3rd: 36 km/h (22 mi/h)
3rd
→
4th: 50 km/h (31 mi/h)
4th
→
5th: 60 km/h (37 mi/h)

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EAU18660
NOTE:


The air filter needs more frequent service if you are riding in unusually wet or dusty areas.

Hydraulic brake service

Regularly check and, if necessary, correct the brake fluid level.

Every two years replace the internal components of the brake master cylinder and caliper, and change the brake fluid.

Replace the brake hoses every four years and if cracked or damaged.
25

*
Front and rear brake
switches

Check operation.
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26

Moving parts and cables

Lubricate.
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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.
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28

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Lights, signals and
switches

Check operation.

Adjust headlight beam.
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NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (
×× × ×
1000 km)
ANNUAL
CHECK
1 6 12 18 24

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To install the panel
Place the panel in the original position.

EAU19602
Checking the spark plug
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.
To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
NOTE:

If the spark plug shows a distinctly dif-
ferent color, the engine could be defec-
tive. Do not attempt to diagnose such
problems yourself. Instead, have a
Yamaha dealer check the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
1. Spark plug cap
1

1. Spark plug wrench
1

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necessary.
To install the spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
2. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.3. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
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 speci-
fied torque as soon as possible.
4. Install the spark plug cap.
EAU19792
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 ele-
ment cleaned at the intervals specified
in the periodic maintenance and lubri-
cation chart.
To check the engine oil level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
NOTE:

Make sure that the vehicle 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 set-
tles, and then check the oil level
through the check window located
at the bottom-right side of the Specified spark plug:
NGK/DR8EA
1. Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1

Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf,
12.7 ft·lbf)

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WARNING

EWA10680

After adjusting the drive chain
slack or removing and installing
the rear wheel, always check the
brake pedal free play.

If proper adjustment cannot be
obtained as described, have a
Yamaha dealer make this ad-
justment.

After adjusting the brake pedal
free play, check the operation of
the brake light.
EAU22270
Adjusting the rear brake light
switch
The rear brake light switch, which is ac-
tivated by the brake pedal, is properly
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 earlier,
turn the adjusting nut in direction (a). To
make the brake light come on later, turn
the adjusting nut in direction (b).
EAU22380
Checking the front brake pads
and rear brake shoes
The front brake pads and the rear brake
shoes must be checked for wear at the
intervals specified in the periodic main-
tenance and lubrication chart.
EAU22430
Front brake pads
Each front brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear
indicator grooves have almost disap-
1. Brake pedal free play adjusting nut
1
(a)
(b)

1. Rear brake light switch
2. Rear brake light switch adjusting nut1
2
(a)
(b)

1. Brake pad wear indicator groove
1
1

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4. If the drive chain slack is incorrect,
adjust it as follows.

EAU22830
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 loos-
en the drive chain, turn the adjust-
ing plate on each side of the
swingarm in direction (b), and then
push the rear wheel forward.
NOTE:

Make sure that both adjusting plates
are in the same position for proper
wheel alignment.
CAUTION:

ECA10570
Improper drive chain slack will over-
load 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 6-18.)
WARNING

EWA10660
After adjusting the brake pedal free
play, check the operation of the
brake light.
1. Drive chain slack
1

1. Brake pedal free play adjusting nut
2. Axle nut
3. Drive chain slack adjusting plate32
1
(a)
(b)
Tightening torque:
Axle nut:
90 Nm (9.0 m·kgf, 65.1 ft·lbf)

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CAUTION:

ECA10640
Do not use a fuse of a higher amper-
age rating than recommended 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.
EAU23792
Replacing the headlight bulb
This model is equipped with a quartz
bulb headlight. If the headlight bulb
burns out, replace it as follows.
1. Remove the headlight unit by re-
moving the screws.
2. Disconnect the headlight coupler,
and then remove the bulb cover.3. Unhook the headlight bulb holder,
and then remove the defective
bulb. Specified fuse:
20.0 A
1. Screw
1(×2)

1. Headlight coupler
2. Bulb cover
1
2

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WARNING

EWA10790
Headlight bulbs get very hot. There-
fore, keep flammable products away
from a lit headlight bulb, and do not
touch the bulb until it has cooled
down.
4. Place a new headlight bulb into po-
sition, and then secure it with the
bulb holder.
CAUTION:

ECA10660
Do not touch the glass part of the
headlight bulb to keep it free from
oil, otherwise the transparency ofthe glass, the luminosity of the bulb,
and the bulb life will be adversely af-
fected. Thoroughly clean off any dirt
and fingerprints on the headlight
bulb using a cloth moistened with al-
cohol or thinner.
5. Install the headlight bulb cover,
and then connect the coupler.6. Install the headlight unit by install-
ing the screws.
7. Have a Yamaha dealer adjust the
headlight beam if necessary.
1. Headlight bulb holder
1

1. Do not touch the glass part of the bulb.
1

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