2001 YAMAHA TW125 check engine

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EAU00629
Adjusting the carburetorThe carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the
necessary professional knowledge
and experience. The adjustment
described in the following section,
however, may be serviced by the
owner as part of routine mainte-
nance.
EC000094
cCThe carburetor has been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
EAU01168
Adjusting the engine idling
speedThe engine idling speed must be
checked and, if necessary, adjusted
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.NOTE:
A diagnostic tachometer is needed to
make this adjustment.1. Attach the tachometer to the
spark plug lead.
2. Start the engine and warm it up
for several minutes at
1,000Ð2,000 r/min while occa-
sionally revving it to 4,000Ð5,000
r/min.NOTE:
The engine is warm when it quickly
responds to the throttle.
To clean the air filter check hose
1. Check the hose at the bottom of
the air filter case for accumulated
dirt or water.
2. If dirt or water is visible, remove
the hose, clean it, and then
install it.1. Air filter check hose
1
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93. Check the engine idling speed
and, if necessary, adjust it to
specification by turning the throt-
tle stop screw. To increase the
engine idling speed, turn the
screw in direction a.To
decrease the engine idling speed,
turn the screw in direction b.
NOTE:
If the specified idling speed cannot
be obtained as described above,
have a Yamaha dealer make the
adjustment.1. Throttle stop screw
1
a
b
Engine idling speed:
1,300Ð1,500 r/min
EAU00634
Adjusting the throttle cable
free playThe throttle cable free play should
measure 3Ð5 mm at the throttle grip.
Periodically check the throttle cable
free play and, if necessary, adjust it
as follows.NOTE:
The engine idling speed must be cor-
rectly adjusted before checking and
adjusting the throttle cable free play.
1. Adjusting nut
2. Locknut
c. Free play1. Loosen the locknut.
2. To increase the throttle cable
free play, turn the adjusting nut
in direction a. To decrease the
throttle cable free play, turn the
adjusting nut in direction b.
3. Tighten the locknut.
1
2
abc
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EAU00637
Adjusting the valve
clearanceThe valve clearance changes with
use, resulting in improper air-fuel mix-
ture and/or engine noise. To prevent
this from occurring, the valve clear-
ance must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
EAU03563
TiresTo maximize the performance, dura-
bility, and safe operation of your
motorcycle, note the following points
regarding the specified tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
EW000082
w8The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the tempera-
ture of the tires equals the
ambient temperature).
8The tire air pressure must be
adjusted in accordance with
the riding speed and with the
total weight of rider, passen-
ger, cargo, and accessories
approved for this model.
Tire air pressure
(measured on cold tires)
Load* Front Rear
150 kPa 150 kPa
Up to 80 kg 1.50 kg/cm
2, 1.50 kg/cm
2,
1.50 bar 1.50 bar
80 kgÐ150 kPa 175 kPa
Maximum *1.50 kg/cm
2, 1.75 kg/cm
2,
1.50 bar 1.75 bar
125 kPa 125 kPa
Off-road riding 1.25 kg/cm
2, 1.25 kg/cm
2,
1.25 bar 1.25 bar
Maximum load* 180 kg
* Total weight of rider, passenger, cargo and
accessories
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EAU03526
To adjust the drive chain slack
1. Loosen the brake pedal free play
adjusting nut and the axle nut.
2. 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.NOTE:
Make sure that both adjusting plates
are in the same position for proper
wheel alignment.1. Axle nut
2. Chain adjusting plate
3. Rear brake pedal free play adjusting nut
21
a
b
3
EC000096
cCImproper 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.3. Tighten the brake pedal free play
adjusting nut, and then tighten
the axle nut to the specified
torque.
4. Adjust the brake pedal free play.
(See page 6-21 for brake pedal
free play adjustment proce-
dures.)
EW000103
wAfter adjusting the brake pedal
free play, check the operation of
the brake light.
EAU01106
Lubricating the drive chainThe drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly
wear out, especially when riding in
dusty or wet areas. Service the drive
chain as follows.
EC000097
cCThe drive chain must be lubricated
after washing the motorcycle or
riding in the rain.1. Remove all dirt and mud from
the drive chain with a brush or
cloth.
2. Spray a drive chain lubricant on
both sides and on the middle of
the chain, making sure that all
side plates and rollers have been
sufficiently oiled.NOTE:
For a thorough cleaning, have a
Yamaha dealer remove the drive
chain and soak it in solvent.
Tightening torque:
Axle nut:
90 Nm (9.0 mákg)
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EAU02962
Checking and lubricating the
cablesThe operation of all control cables
and the condition of the cables
should be checked before each ride,
and the cables and cable ends
should be lubricated if necessary. If a
cable is damaged or does not move
smoothly, have a Yamaha dealer
check or replace it.
EW000112
wDamage to the outer sheath may
interfere with proper cable opera-
tion and will cause the inner cable
to rust. Replace a damaged cable
as soon as possible to prevent
unsafe conditions.
Recommended lubricant:
Engine oil
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EAU03209
Checking and lubricating the
throttle grip and cableThe operation of the throttle grip and
the condition of the throttle cable
should be checked before each ride,
and the cable should be lubricated or
replaced if necessary.NOTE:
Since the throttle grip must be
removed to access the throttle cable
end, the throttle grip and the cable
should always be lubricated at the
same time.1. Remove the throttle grip by
removing the screws.
2. Disconnect the throttle cable,
hold it up, and then apply several
drops of oil to the cable end,
allowing it to trickle into the
sheath.
3. Connect the throttle cable, and
then grease the inside of the
throttle grip housing.
EAU03370
Checking and lubricating the
brake and shift pedalsThe operation of the brake and shift
pedals should be checked before
each ride, and the pedal pivots
should be lubricated if necessary.
Recommended lubricant:
Lithium-soap-based grease
(all-purpose grease)
4. Grease the metal-to-metal con-
tact surface of the throttle grip,
and then install the grip by
installing the screws.
Recommended lubricant:
Throttle cable:
Engine oil
Throttle grip housing and grip:
Lithium-soap-based grease
(all-purpose grease)
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EAU02939
Checking the front forkThe condition and operation of the
front fork must be checked as follows
at the intervals specified in the peri-
odic maintenance and lubrication
chart.
To check the condition
EW000115
wSecurely support the motorcycle
so that there is no danger of it
falling over.Check the inner tubes for scratches,
damage and excessive oil leakage.To check the operation
1. Place the motorcycle on a level
surface and hold it in an upright
position.
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and
rebounds smoothly.
EC000098
cCIf any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or
repair it.
EAU00794
Checking the steeringWorn or loose steering bearings may
cause danger. Therefore, the opera-
tion of the steering must be checked
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
1. Place a stand under the engine
to raise the front wheel off the
ground.
EW000115
wSecurely support the motorcycle
so that there is no danger of it
falling over.
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EAU01579
Supporting the motorcycleSince this model is not equipped with
a centerstand, follow these precau-
tions when removing the front and
rear wheel or performing other main-
tenance requiring the motorcycle to
stand upright. Check that the motor-
cycle is in a stable and level position
before starting any maintenance. A
strong wooden box can be placed
under the engine for added stability.
To service the front wheel
1. Stabilize the rear of the motorcy-
cle by using a motorcycle stand
or, if an additional motorcycle
stand is not available, by placing
a jack under the frame in front of
the rear wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand. 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
screws.
EC000108
cCDo not overtighten the screws,
otherwise the lens may break.1. Bulb
1
EAU01623
Replacing the tail/brake light
bulb1. Remove the tail/brake light lens
by removing the screws.1. Screw (´2)
1
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