transmission YAMAHA TW125 2004 Owners Manual

INSTRUMENT AND CONTROL FUNCTIONS
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EAU10450
Main switch
The main switch controls the ignition
and lighting systems. The various main
switch positions are described below.
EAU10570
ON
All electrical circuits are supplied with
power; the meter lighting, taillight and
auxiliary light come on, and the engine
can be started. The key cannot be re-
moved.
NOTE:

The headlight comes on automatically
when the engine is started and stays on
until the key is turned to “OFF”.
EAU10660
OFF
All electrical systems are off. The key
can be removed.
EAU10980
Indicator lights
EAU11020
Turn signal indicator light “”
This indicator light flashes when the
turn signal switch is pushed to the left or
right.
EAU11060
Neutral indicator light “”
This indicator light comes on when the
transmission is in the neutral position.
EAU11080
High beam indicator light “”
This indicator light comes on when the
high beam of the headlight is switched
OFFON

1. Turn signal indicator light “ ”
2. High beam indicator light “ ”
3. Neutral indicator light “ ”
3
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INSTRUMENT AND CONTROL FUNCTIONS
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EAU12820
Clutch lever
The clutch lever is located at the left
handlebar grip. To disengage the
clutch, pull the lever toward the handle-
bar grip. To engage the clutch, release
the lever. The lever should be pulled
rapidly and released slowly for smooth
clutch operation.
The clutch lever is equipped with a
clutch switch, which is part of the igni-
tion circuit cut-off system. (See
page 3-11.)
EAU12870
Shift pedal
The shift pedal is located on the left
side of the engine and is used in com-
bination with the clutch lever when
shifting the gears of the 5-speed con-
stant-mesh transmission equipped on
this motorcycle.
EAU12890
Brake lever
The brake lever is located at the right
handlebar grip. To apply the front
brake, pull the lever toward the handle-
bar grip.
1. Clutch lever
1

1. Shift pedal1
1. Brake lever
1

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INSTRUMENT AND CONTROL FUNCTIONS
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EAU15300
Sidestand
The sidestand is located on the left side
of the frame. Raise the sidestand or
lower it with your foot while holding the
vehicle upright.
NOTE:

The built-in sidestand switch is part of
the ignition circuit cut-off system, which
cuts the ignition in certain situations.
(See further down for an explanation of
the ignition circuit cut-off system.)
WARNING

EWA10240
The vehicle must not be ridden with
the sidestand down, or if the side-
stand cannot be properly moved up
(or does not stay up), otherwise the
sidestand could contact the ground
and distract the operator, resulting
in a possible loss of control.
Yamaha’s ignition circuit cut-off
system has been designed to assist
the operator in fulfilling the respon-
sibility of raising the sidestand be-
fore starting off. Therefore, checkthis system regularly as described
below and have a Yamaha dealer re-
pair it if it does not function proper-
ly.
EAU15311
Ignition circuit cut-off system
The ignition circuit cut-off system (com-
prising the sidestand switch, clutch
switch and neutral switch) has the fol-
lowing functions.

It prevents starting when the trans-
mission is in gear and the side-
stand is up, but the clutch lever is
not pulled.

It prevents starting when the trans-
mission is in gear and the clutch le-
ver is pulled, but the sidestand is
still down.

It cuts the running engine when the
transmission is in gear and the sid-
estand is moved down.
Periodically check the operation of the
ignition circuit cut-off system according
to the following procedure.
WARNING

EWA10250
If a malfunction is noted, have a
Yamaha dealer check the system be-
fore riding.

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INSTRUMENT AND CONTROL FUNCTIONS
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With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is turned on.
3. Turn the key on.
4. Shift the transmission into the neutral position.
5. Push the start switch.
Does the engine start?
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
10. Move the sidestand up.
11. Keep the clutch lever pulled.
12. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can be ridden.
This check is most reliable if performed with
a warmed-up engine.The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The sidestand switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The clutch switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
YES NO YES NO YES NONOTE:

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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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OPERATION AND IMPORTANT RIDING POINTS
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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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PERIODIC MAINTENANCE AND MINOR REPAIR
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brake fluid level goes down sud-
denly, have a Yamaha dealer
check the cause.

EAU22720
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addition,
have the oil seals of the brake master
cylinder and caliper as well as the
brake hose replaced at the intervals
listed below or whenever they are dam-
aged or leaking.

Oil seals: Replace every two
years.

Brake hose: Replace every four
years.
EAU22760
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22770
To check the drive chain slack
1. Place the motorcycle on a level
surface and hold it in an upright po-
sition.
NOTE:

When checking and adjusting the drive
chain slack, the motorcycle should be
positioned straight up and there should
be no weight on it.
2. Shift the transmission into the neu-
tral position.
3. Move the rear wheel by pushing
the motorcycle to locate the tight-
est portion of the drive chain, and
then measure the drive chain slack
as shown.
Drive chain slack:
35.0–60.0 mm (1.38–2.36 in)

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SPECIFICATIONS
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EAU26333
Dimensions:
Overall length:
2135 mm (84.1 in)
Overall width:
820 mm (32.3 in)
Overall height:
1120 mm (44.1 in)
Seat height:
820 mm (32.3 in)
Wheelbase:
1350 mm (53.1 in)
Ground clearance:
255 mm (10.04 in)
Minimum turning radius:
2100 mm (82.7 in)
Weight:
With oil and fuel:
127.0 kg (280 lb)
Engine:
Engine type:
Air cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
125.0 cm
3

(7.63 cu.in)
Bore
×
stroke:
57.0
×
48.8 mm (2.24
×
1.92 in)
Compression ratio:
10.00 :1
Starting system:
Electric starter
Lubrication system:
Wet sump

Engine oil:
Type:
SAE10W30 or SAE10W40 or SAE15W40
or SAE20W40 or SAE20W50
Recommended engine oil grade:
API service SE, SF, SG type or higher
Engine oil quantity:
Without oil filter element removal:
1.00 L (1.06 US qt) (0.88 Imp.qt)
With oil filter element removal:
1.10 L (1.16 US qt) (0.97 Imp.qt)
Air filter:
Air filter element:
Wet element
Fuel:
Recommended fuel:
Regular unleaded gasoline only
Fuel tank capacity:
7.0 L (1.85 US gal) (1.54 Imp.gal)
Fuel reserve amount:
1.7 L (0.45 US gal) (0.37 Imp.gal)
Carburetor:
Manufacturer:
TEIKEI
Type x quantity:
MV28 x 1
Spark plug(s):
Manufacturer/model:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Clutch:
Clutch type:
Wet, multiple-disc
Transmission:
Primary reduction system:
Spur gear
Primary reduction ratio:
74/20 (3.700)
Secondary reduction system:
Chain drive
Secondary reduction ratio:
51/14 (3.643)
Transmission type:
Constant mesh 5-speed
Operation:
Left foot operation
Gear ratio:
1st:
36/16 (2.250)
2nd:
31/21 (1.476)
3rd:
27/24 (1.125)
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40

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