YAMAHA TW125 2002 Service Manual

6-10
PERIODIC MAINTENANCE AND MINOR REPAIR
6
ECA00039
cCWhen removing the engine oil
drain bolt, the O-ring, compression
spring, and oil strainer will fall out.
Take care not to lose these parts.
12 3
1. Strainer
2. Compression spring
3. O-ring
NOTE:
Skip steps 4–9 if the oil filter element
is not being cleaned.4. Remove the oil filter element
drain bolt to drain the oil from the
oil filter element.
5. Remove the oil filter element
cover by removing the bolts.
1
2
3
1. Oil filter element drain bolt
2. Oil filter element cover
3. Oil filter element cover bolt (×2)
1
1. Engine oil drain bolt
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6-11
PERIODIC MAINTENANCE AND MINOR REPAIR
6 6. 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 2
2
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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6-12
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04216
Cleaning the air filter ele-
ment and check hoseThe 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)
ECA00105
cC8In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives
with the oil or use oils of grade
“CD” or higher. In addition, do
not use oils labeled “ENERGY
CONSERVING
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.
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6-13
PERIODIC MAINTENANCE AND MINOR REPAIR
6 3. Pull the air filter element out.
4. Remove the sponge material
from the air filter element frame,
clean it with solvent, and then
squeeze the remaining solvent
out.
1
2
1. Sponge material
2. Air filter element frame
5. Apply oil of the recommended
type to the entire surface of the
sponge material, and then
squeeze the excess oil out.NOTE:
The sponge material should be wet
but not dripping.6. Pull the sponge material over the
air filter element frame.
7. Insert the element into the air fil-
ter case.
EC000082
cC8Make sure that the air filter ele-
ment is properly seated in the
air filter case.
8The engine should never be
operated without the air filter
element installed, otherwise
the piston and/or cylinder may
become excessively worn.8. Install the air filter case cover by
installing the screws.
9. Install the panel.
Recommended oil:
Engine oil
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6-14
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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 1,000–
2,000 r/min while occasionally
revving it to 4,000–5,000 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
1. Air filter check hose
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6-15
PERIODIC MAINTENANCE AND MINOR REPAIR
6 3. 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
a
b
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 playThe 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.
Engine idling speed:
1,450–1,650 r/min
a
a. Throttle cable free play
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6-16
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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.
EAU04401
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
Up to 90 kg150 kPa
(1.50 kgf/cm
2,
1.50 bar)150 kPa
(1.50 kgf/cm
2,
1.50 bar)
90 kg–
maximum150 kPa
(1.50 kgf/cm
2,
1.50 bar)175 kPa
(1.75 kgf/cm
2,
1.75 bar)
Maximum load* 180 kg
* Total weight of rider, passenger, cargo and
accessories
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6-17
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EWA00040
wBecause loading has an enormous
impact on the handling, braking,
performance and safety character-
istics of your motorcycle, you
should keep the following precau-
tions in mind.
8NEVER OVERLOAD THE
MOTORCYCLE! Operation of
an overloaded motorcycle may
result in tire damage, loss of
control, or severe injury. Make
sure that the total weight of
rider, passenger, cargo, and
accessories does not exceed
the specified maximum load
for the vehicle.
8Do not carry along loosely
packed items, which can shift
during a ride.
8Securely pack the heaviest
items close to the center of the
motorcycle and distribute the
weight evenly on both sides.Tire inspection
The tires must be checked before
each ride. If the center tread depth
reaches the specified limit, if the tire
has a nail or glass fragments in it, or
if the sidewall is cracked, have a
Yamaha dealer replace the tire imme-
diately.
NOTE:
The tire tread depth limits may differ
from country to country. Always com-
ply with the local regulations.
1a
1. Tire side wall
a. Tire tread depth
8Adjust the tire air pressure
with regard to the load.
8Check the tire condition and
air pressure before each ride.
Minimum tire tread depth
(front and rear)1.6 mm
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6-18
PERIODIC MAINTENANCE AND MINOR REPAIR
6Tire information
This motorcycle is equipped with tube
tires.
EW000078
w8The front and rear tires should
be of the same make and
design, otherwise the handling
characteristics of the motorcy-
cle cannot be guaranteed.
8After extensive tests, only the
tires listed below have been
approved for this model by
Yamaha Motor Co., Ltd.
EAU00685
Spoke wheelsTo maximize the performance, dura-
bility, and safe operation of your
motorcycle, note the following points
regarding the specified wheels.
8The wheel rims should be
checked for cracks, bends or
warpage, and the spokes for
looseness or damage before
each ride. If any damage is
found, have a Yamaha dealer
replace the wheel. Do not
attempt even the smallest repair
to the wheel. A deformed or
cracked wheel must be replaced.
8The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced.
An unbalanced wheel can result
in poor performance, adverse
handling characteristics, and a
shortened tire life.
EAU00681
w8Have a Yamaha dealer replace
excessively worn tires.
Besides being illegal, operat-
ing the motorcycle with exces-
sively worn tires decreases
riding stability and can lead to
loss of control.
8The replacement of all wheel-
and brake-related parts,
including the tires, should be
left to a Yamaha dealer, who
has the necessary profession-
al knowledge and experience.
8It is not recommended to
patch a punctured tube. If
unavoidable, however, patch
the tube very carefully and
replace it as soon as possible
with a high-quality product.
FRONT
Manufacturer Size TypeBRIDGESTONE
130/80-18 66P
TW-203
130/80-18 M/C 66P
REAR
Manufacturer Size Type
BRIDGESTONE
180/80-14 M/C 78P TW-204
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6-19
PERIODIC MAINTENANCE AND MINOR REPAIR
6 8Ride at moderate speeds after
changing a tire since the tire sur-
face must first be “broken in” for
it to develop its optimal charac-
teristics.3. If the specified clutch lever free
play could be obtained as
described above, tighten the
locknut and skip the rest of the
procedure, otherwise proceed as
follows.
4. Fully turn the adjusting bolt at the
clutch lever in direction ato
loosen the clutch cable.
EAU00694
Adjusting the clutch lever
free playThe clutch lever free play should
measure 10–15 mm as shown.
Periodically check the clutch lever
free play and, if necessary, adjust it
as follows.
1. Loosen the locknut at the clutch
lever.
2. To increase the clutch lever free
play, turn the adjusting bolt in
direction a. To decrease the
clutch lever free play, turn the
adjusting bolt in direction b.c1
2
ab
1. Locknut (clutch lever)
2. Adjusting bolt
c. Free play
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