check engine YAMAHA TW125 2003 User Guide

6-9
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04616
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 element cleaned at the intervals
specified in the periodic maintenance
and lubrication chart.
To check the engine oil level
1. Place the motorcycle on a level
surface and hold it in an upright
position.
NOTE:
Make sure that the motorcycle 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
settles, and then check the oil
level through the check window
located at the bottom-right side
of the crankcase.
NOTE:
The engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is below the min-
imum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
2
3 1
1. Engine oil level check window
2. Maximum level mark
3. Minimum level mark
To change the engine oil (with or
without oil filter element cleaning)
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the
engine to collect the used oil.
3. Remove the engine oil filler cap
and drain bolt to drain the oil
from the crankcase.
1
1. Engine oil filler cap
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PERIODIC MAINTENANCE AND MINOR REPAIR
66. Remove the oil filter element and
O-rings.
7. Check the O-ring for damage
and replace it if necessary.
8. Clean the oil filter element with
solvent, and then install it.
NOTE:
Check the oil filter element for dam-
age and replace it if necessary.
9. Install the oil filter element cover
by installing the bolts and the
drain bolt, then tightening them
to the specified torques.
1 22
1. Oil filter element
2. O-ring (×2)
NOTE:
Make sure that the O-rings are prop-
erly seated.
10. Clean the oil strainer with sol-
vent, and then check it for dam-
age and replace it if necessary.
11. Install the oil strainer, compres-
sion spring, O-ring and engine oil
drain bolt, and then tighten the
drain bolt to the specified torque.12. Add the specified amount of the
recommended engine oil, and
then install and tighten the oil
filler cap. Tightening torques:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf)
Oil filter element drain bolt:
10 Nm (1.0 m·kgf)
Tightening torque:
Engine oil drain bolt:
43 Nm (4.3 m·kgf)
Recommended engine oil:
See page 8-1.
Oil quantity:
Without oil filter element
removal:
1.0 L
With oil filter element removal:
1.1 L
Total amount (dry engine):
1.3 L
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
ECA00133
cC
8In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives.
Do not use oils with a diesel
specification of “CD” or oils of
a higher quality than specified.
In addition, do not use oils
labeled “ENERGY CONSERV-
ING
II” or higher.
8Make sure that no foreign
material enters the crankcase.
13. Start the engine, and then let it
idle for several minutes while
checking it for oil leakage. If oil is
leaking, immediately turn the
engine off and check for the
cause.
14. Turn the engine off, and then
check the oil level and correct it if
necessary.
EAU04216
Cleaning the air filter
element and check hose
The air filter element should be
cleaned at the intervals specified in
the periodic maintenance and lubrica-
tion chart. Clean the air filter element
more frequently if you are riding in
unusually wet or dusty areas. In addi-
tion, the air filter check hose must be
frequently checked and cleaned if
necessary.
To clean the air filter element
1. Remove panel A. (See page 6-5
for panel removal and installation
procedures.)2. Remove the air filter case cover
by removing the screws.
1
2
2
1. Air filter case cover
2. Screw (×4)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6 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
1. Air filter check hose
EAU00629
Adjusting the carburetor
The 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
cC
The 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.
EAU04757
Adjusting the engine idling
speed
The engine idling speed must be
checked and, if necessary, adjusted
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
The engine should be warm before
making this adjustment.
NOTE:
8The engine is warm when it
quickly responds to the throttle.
8A diagnostic tachometer is need-
ed to make this adjustment.
1. Attach the tachometer to the
spark plug lead.
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PERIODIC MAINTENANCE AND MINOR REPAIR
62. 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.
1
ab
1. Throttle stop screw
NOTE:
If the specified idling speed cannot
be obtained as described above,
have a Yamaha dealer make the
adjustment.
EAU00635
Adjusting the throttle cable
free play
The throttle cable free play should
measure 3–5 mm at the throttle grip.
Periodically check the throttle cable
free play and, if necessary, have a
Yamaha dealer adjust it.
a
a. Throttle cable free play
Engine idling speed:
1,450–1,650 r/min
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00637
Adjusting the valve
clearance
The 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.
EAU04401
Tires
To 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
w
8The 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
Up to 90 kg150 kPa
(1.50 kgf/cm
2,
1.50 bar)150 kPa
(1.50 kgf/cm2,
1.50 bar)
90 kg–maximum150 kPa
(1.50 kgf/cm
2,
1.50 bar)175 kPa
(1.75 kgf/cm2,
1.75 bar)
Maximum load* 180 kg
* Total weight of rider, passenger, cargo and
accessories
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04369
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 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.
32
a
b
1
1. Brake pedal free play adjusting nut
2. Axle nut
3. Drive chain adjusting plate
NOTE:
Make sure that both adjusting plates
are in the same position for proper
wheel alignment.
EC000096
cC
Improper 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.
4. Tighten the axle nut to the speci-
fied torque.5. Adjust the brake pedal free play.
(See page 6-21 for brake pedal
free play adjustment proce-
dures.)
EW000103
w
After adjusting the brake pedal
free play, check the operation of
the brake light.
Tightening torque:
Axle nut:
90 Nm (9.0 m·kgf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01106
Lubricating the drive chain
The 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
cC
The 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.
EAU02962
Checking and lubricating the
cables
The 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.
Recommended lubricant:
Engine oil
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00794
Checking the steering
Worn 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
w
Securely support the motorcycle
so that there is no danger of it
falling over.
2. Hold the lower ends of the front
fork legs and try to move them
forward and backward. If any
free play can be felt, have a
Yamaha dealer check or repair
the steering.
EAU01144
Checking the wheel bearings
The front and rear wheel bearings
must be checked at the intervals
specified in the periodic maintenance
and lubrication chart. If there is play
in the wheel hub or if the wheel does
not turn smoothly, have a Yamaha
dealer check the wheel bearings.
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PERIODIC MAINTENANCE AND MINOR REPAIR
62. 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
cC
Do not overtighten the screws,
otherwise the lens may break.
1
1. Bulb
EAU01579
Supporting the motorcycle
Since 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.To service the rear wheel
Raise the rear wheel off the ground
by using a motorcycle stand or, if a
motorcycle stand is not available, by
placing a jack either under each side
of the frame in front of the rear wheel
or under each side of the swingarm.
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