2001 YAMAHA TW125 transmission

3-1
EAU00027
INSTRUMENT AND CONTROL FUNCTIONS
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23
4
5
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EAU00028
Main switchThe main switch controls the ignition
and lighting systems. The various
main switch positions are described
below.
EAU00036
ON
All electrical systems are supplied
with power, and the engine can be
started. The key cannot be removed.
EAU00038
OFF
All electrical systems are off. The key
can be removed.
EAU00056
Indicator lights
EAU00057
Turn signal indicator light Ò5Ó
This indicator light flashes when the
turn signal switch is pushed to the left
or right.
EAU00061
Neutral indicator light ÒNÓ
This indicator light comes on when
the transmission is in the neutral
position.1. Turn indicator light Ò5Ó
2. High beam indicator light Ò&Ó
3. Neutral indicator light ÒNÓ
EAU00063
High beam indicator light Ò&Ó
This indicator light comes on when
the high beam of the headlight is
switched on.
OFFON
3
12
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3-4
INSTRUMENT AND CONTROL FUNCTIONS
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EAU00157
Shift pedalThe shift pedal is located on the left
side of the engine and is used in
combination with the clutch lever
when shifting the gears of the
5-speed constant-mesh transmission
equipped on this motorcycle.1. Shift pedal
N. Neutral
EAU00152
Clutch leverThe clutch lever is located at the left
handlebar grip. To disengage the
clutch, pull the lever toward the han-
dlebar 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 for an explanation of the ignition
circuit cut-off system.)1. Clutch lever
EAU00158
Brake leverThe brake lever is located at the right
handlebar grip. To apply the front
brake, pull the lever toward the han-
dlebar grip.1. Brake lever
1
1
1
N5
4
3
2
1
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3-11
INSTRUMENT AND CONTROL FUNCTIONS
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9
EAU00330
SidestandThe sidestand is located on the left
side of the frame. Raise the side-
stand or lower it with your foot while
holding the motorcycle upright.NOTE:
The built-in sidestand switch is part of
the ignition circuit cut-off system,
which cuts the ignition in certain situ-
ations. (See further down for an
explanation of the ignition circuit cut-
off system.)
EW000044
wThe motorcycle must not be ridden
with the sidestand down, or if the
sidestand cannot be properly
moved up (or does not stay up),
otherwise the sidestand could con-
tact the ground and distract the
operator, resulting in a possible
loss of control. YamahaÕs ignition
circuit cut-off system has been
designed to assist the operator in
fulfilling the responsibility of rais-
ing the sidestand before starting
off. Therefore, check this system
regularly as described below and
have a Yamaha dealer repair it if it
does not function properly.
EAU00331
Ignition circuit cut-off
systemThe ignition circuit cut-off system
(comprising the sidestand switch,
clutch switch and neutral switch) has
the following functions.
8It prevents starting when the
transmission is in gear and the
sidestand is up, but the clutch
lever is not pulled.
8It prevents starting when the
transmission is in gear and the
clutch lever is pulled, but the
sidestand is still down.
8It cuts the running engine when
the sidestand is moved down.
Periodically check the operation of
the ignition circuit cut-off system
according to the following procedure.
EW000045
wIf a malfunction is noted, have a
Yamaha dealer check the system
before riding.
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3-12
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 set to Ò
#Ó.
3. Turn the key to ÒONÓ.
4. Shift the transmission into the neutral position.
5. Push the start switch.
Does the engine start?
The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
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 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.
NO
NOTE:This check is most reliable if performed with
a warmed-up engine.
YESYES NO
The system is OK. The motorcycle can be ridden.
YES NO
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5-1
EAU00372
OPERATION AND IMPORTANT RIDING POINTS
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EAU00373
w8Become 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.
EAU03515
Starting the engineIn 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.
EW000054
w8Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-12.
8Never ride with the sidestand
down.
1. Turn the fuel cock lever to ÒONÓ.
2. Turn the key to ÒONÓ and make
sure that the engine stop switch
is set to Ò#Ó.
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.1. Arrow mark positioned over ÒONÓ
ON
FUEL
RES
OFF
1
ON
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5-3
OPERATION AND IMPORTANT RIDING POINTS
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EC000048
cC8Even 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.
1
N5
4
3
2
1
EAU00423
ShiftingShifting 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.1. Shift pedal
N. Neutral
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).
Shift point (km/h)
1st ®2nd 23
2nd ®3rd 36
3rd ®4th 50
4th ®5th 60
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6-25
PERIODIC MAINTENANCE AND MINOR REPAIR
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EAU00744
Drive chain slackThe drive chain slack should be
checked before each ride and adjust-
ed if necessary.
To check the drive chain slack
1. Place the motorcycle on a level
surface and hold it in an upright
position.NOTE:
When checking and adjusting the
drive chain slack, the motorcycle
should be positioned straight up and
there should be no weight on it.
a. Drive chain slack2. Shift the transmission into the
neutral 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.
4. If the drive chain slack is incor-
rect, adjust it as follows.
a
Drive chain slack:
35Ð60 mm
EAU03238
Changing the brake fluidHave a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion 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 it is damaged or leaking.
8Oil seals: Replace every two
years.
8Brake hose: Replace every four
years.
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8-2
SPECIFICATIONS
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Fuel
Type Regular unleaded gasoline
Fuel tank capacity 7.0 L
Reserve amount 1.0 L
Carburetor
Manufacturer TEIKEI
Model ´quantity Y24P ´1
Spark plug
Manufacturer/Type NGK/DR8EA
Gap 0.6Ð0.7 mm
Clutch typeWet, multiple-disc
Transmission
Primary reduction system Spur gear
Primary reduction ratio 74/20 (3.700)
Secondary reduction system Chain drive
Secondary reduction ratio 3.571
Number of drive chain
sprocket teeth (rear/front) 50/14
Transmission type Constant mesh 5-speed
Operation Left foot operationGear ratio 1st 2.250
2nd 1.476
3rd 1.125
4th 0.926
5th 0.793
Chassis
Frame type Diamond
Caster angle 26¡
Trail 95 mm
Tires
Type With tube
Front
Size 130/80-18 66P
Manufacturer/ BRIDGESTONE / TW31
model
Rear
Size 180/80-14M/C 78P
Manufacturer/ BRIDGESTONE / TW34
model
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