2001 YAMAHA TW125 engine

3-8
INSTRUMENT AND CONTROL FUNCTIONS
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EAU03032
Starter (choke) knob Ò1ÓStarting a cold engine requires a rich-
er air-fuel mixture, which is supplied
by the starter (choke).
Move the knob in direction ato turn
on the starter (choke).
Move the knob in direction bto turn
off the starter (choke).1. Starter (choke) knob Ò1Ó
EAU02934
Steering lockTo lock the steering
1. Turn the handlebar all the way to
the right.
2. Open the steering lock cover,
and then insert the key.
3. Turn the key 1/8 turn counter-
clockwise, push it in while turning
the handlebar slightly to the left,
and then turn the key 1/8 turn
clockwise.
4. Check that the steering is locked,
remove the key, and then close
the lock cover.1. Steering lock
2. Cover
To unlock the steering
1. Open the steering lock cover,
and then insert the key.
2. Push the key in, turn it 1/8 turn
counterclockwise so that it
moves out, and then release it.
3. Remove the key, and then close
the lock cover.
a
b
1
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3-11
INSTRUMENT AND CONTROL FUNCTIONS
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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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4-1
EAU01114
PRE-OPERATION CHECKS
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9 The condition of a vehicle is the ownerÕs responsibility. Vital components can start to deteriorate quickly and unexpect-
edly, even if the vehicle remains unused (for example, as a result of exposure to the elements). Any damage, fluid leak-
age or loss of tire air pressure could have serious consequences. Therefore, it is very important, in addition to a thor-
ough visual inspection, to check the following points before each ride.
EAU03328
Pre-operation check list
ITEM CHECKS PAGE
Front brake9Check operation, free play, fluid level and vehicle for fluid leakage.
3-4, 6-20, 6-23Ð6-25
9Fill with DOT 4 brake fluid if necessary.
Rear brake9Check operation, condition and free play.
3-5, 6-21Ð6-239Adjust if necessary.
Clutch9Check operation, condition and free play.
3-4, 6-19Ð6-209Adjust if necessary.
Throttle grip and housing9Check smooth operation.
6-15, 6-289Lubricate if necessary.
Engine oil9Check oil level.
6-9Ð6-129Add oil if necessary.
Drive chain9Check chain slack and condition.
6-25Ð6-279Adjust if necessary.
Wheels and tires9Check tire air pressure, for wear, damage and spoke tightness.
6-16Ð6-199Tighten spokes if necessary.
Brake and shift pedal shafts9Check smooth operation.
6-289Lubricate if necessary.
Brake and clutch lever pivots9Check smooth operation.
6-299Lubricate if necessary.
Sidestand pivot9Check smooth operation.
6-299Lubricate if necessary.
Chassis fasteners9Make sure that all nuts, bolts and screws are properly tightened.
Ñ
9Tighten if necessary.
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5-1
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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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5-2
OPERATION AND IMPORTANT RIDING POINTS
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94. Turn the starter (choke) on and
completely close the throttle.
(See page 3-8 for starter (choke)
operation.)
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
engine more than 10 seconds on any
one attempt.
6. After starting the engine, move
the starter (choke) knob/lever
back halfway.
ECA00055
cCFor maximum engine life, always
warm the engine up before starting
off. Never accelerate hard when
the engine is 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.
EAU01258
Starting a warm engineFollow the same procedure as for
starting a cold engine with the excep-
tion that the starter (choke) is not
required when the engine is warm.
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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.
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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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5-4
OPERATION AND IMPORTANT RIDING POINTS
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EAU00424
Tips for reducing fuel
consumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Thoroughly warm up the engine.
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).
EAU01128
Engine break-inThere is never a more important peri-
od in the life of your engine than the
period between 0 and 1,600 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 1,600 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.
EAU01500
0Ð1,000 km
Avoid prolonged operation above 1/3
throttle.
1,000Ð1,600 km
Avoid prolonged operation above 1/2
throttle.
EC000057
cCAfter 1,000 km of operation, the
engine oil must be changed, the oil
filter cartridge/element replaced,
and the oil strainer cleaned.1,600 km and beyond
The vehicle can now be operated
normally.
EC000049
cCIf any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealer
check the vehicle.
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