2000 YAMAHA TW125 engine

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*: Since these items require special tools, data and technical skills, they should be serviced by a Yamaha dealer.
EAU02970
NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake system
8When disassembling the master cylinder or caliper, always replace the brake fluid. Check the brake fluid
level regularly and fill as required.
8Replace the oil seals on the inner parts of the master cylinder and caliper every two years.
8Replace the brake hoses every four years or if cracked or damaged.
Every Every
6,000 km 12,000 km
No. ITEM CHECKS AND MAINTENANCE JOBSINITIAL or or
1,000 km 6 months 12 months
(Whichever (Whichever
comes first) comes first)
21 * Carburetor9Check engine idling speed and starter operation.
ÖÖÖ
9Adjust if necessary.
9Check oil level and vehicle for oil leakage.
22 Engine oil9Correct if necessary.ÖÖÖ
9Change. (Warm engine before draining.)
23Engine oil filter element9Clean or replace if necessary.ÖÖ
24 * Engine oil strainer9Clean or replace if necessary.ÖÖ
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EAU01833Spark plug
Removal
1. Remove the spark plug cap.
2. Use the spark plug wrench in
the tool kit to remove the spark
plug as shown.
1. Spark plug wrench
Inspection
The spark plug is an important
engine component and is easy to
inspect. The condition of the spark
plug can indicate the condition of
the engine.
The ideal color on the white insula-
tor around the center electrode is a
medium-to-light tan color for a
motorcycle that is being ridden
normally.
Do not attempt to diagnose such
problems yourself. Instead, take
the motorcycle to a Yamaha deal-
er. You should periodically remove
and inspect the spark plug because
heat and deposits will cause any
spark plug to slowly break down
and erode. If electrode erosion
becomes excessive, or if carbon
and other deposits are excessive,
you should replace the spark plug
with the specified plug.
Specified spark plug:
DR8EA (NGK)
12
1
EAU01145Cowling C
To remove
Remove the cowling screw and
pull outward on the areas shown.
To install
Place in the original position and
install the screw.
1. Cowling C
2. Screw
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Installation
1. Measure the electrode gap
with a wire thickness gauge
and, if necessary, adjust the
gap to specification.
2. Clean the gasket surface. Wipe
off any grime from the
threads.
3. Install the spark plug and tight-
en it to the specified torque.
1. Spark plug gap
NOTE:
If a torque wrench is not available
when you are installing a spark
plug, a good estimate of the cor-
rect torque is 1/4 to 1/2 turn past
finger tight. Have the spark plug
tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
EAU00517*
Engine oil
Oil level measurement
1. Place the motorcycle on a level
place and hold it in an upright
position. Warm up the engine
for several minutes.
NOTE:
Be sure the motorcycle is posi-
tioned straight up when checking
the oil level. A slight tilt toward the
side can result in false readings.
Spark plug gap:
0.6 ~ 0.7 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kg)
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92. With the engine stopped,
check the oil level through the
level window located at the
lower part of the right side
crankcase cover.
NOTE:
Wait a few minutes until the oil
level settles before checking.
3. The oil level should be
between the maximum and
minimum marks. If the level is
low, add sufficient oil to raise
it to the proper level.
1. Maximum level mark
2. Minimum level mark
Engine oil replacement
1. Warm up the engine for a few
minutes.
2. Stop the engine. Place an oil
pan under the engine and
remove the oil filler cap.
1. Engine oil filler cap
3. Remove the drain bolts.
1. Engine oil drain bolt
1
1
1
2
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EC000070
cC
When removing the oil drain bolt,
the O-ring, compression spring,
and oil strainer will fall out. Take
care not to lose these parts.
1. Strainer
2. Compression spring
3. O-ring
NOTE:
The oil filter cover is secured by
two screws and a drain bolt.
Remove the drain bolt to drain the
filter cavity.
1. Bolts (´3)
2. Engine oil drain bolt
4. Remove the filter cover screws
and the oil filter cover.
5. Remove the oil filter element
and O-ring.
6. Clean the oil filter and strainer
with solvent. Replace if neces-
sary.
7. Check the O-rings. If damaged,
replace.
8. Install the filter cover, screws
and drain bolts. Tighten the
drain bolts to the specified
tightening torques.
NOTE:
Make sure the O-ring is seated
properly.
1. Oil filter element
2. O-ring
12 3
1 21
2
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EAU01501*Air filter
The air filter should be cleaned at
the specified intervals. It should be
cleaned more frequently when rid-
ing in unusually wet or dusty
areas.
Air filter element cleaning
1. Remove panel A. (See page
6-6 for removal and installa-
tion procedures.)
2. Remove the air filter case fit-
ting screws and the filter case
cover.
1. Air filter case cover
2. Screw (´4)EC000066
cC
8Do not put in any chemical
additives. Engine oil also lubri-
cates the clutch and additives
could cause clutch slippage.
8Be sure no foreign material
enters the crankcase.
10. Start the engine and warm up
for a few minutes. While
warming up, check for oil leak-
age. If oil leakage is found,
stop the engine immediately
and check for the cause.
EC000071
cC
Before reinstalling the oil drain
bolt, do not forget to install the O-
ring, compression spring, and oil
strainer in position.
9. Fill the engine with oil. Install
the oil filler cap and tighten. Tightening torque:
Drain bolt:
43 Nm (4.3 m·kg)
Filter cover screw:
7.0 Nm (0.7 m·kg)
Drain bolt (filter cover):
10 Nm (1.0 m·kg)
Recommended oil:
See page 8-1.
Total amount:
1.3 L
Periodic oil change:
1.0 L
With oil filter replacement:
1.1 L
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9 3. Remove the air filter from the
case.
4. Remove the air filter element
from its frame and clean it
with solvent. After cleaning,
remove the remaining solvent
by squeezing the element.
5. Apply recommended oil to the
entire surface of the element
and squeeze out the excess oil.
The element should be wet but
not dripping.
1. Air filter element
2. Air filter element frame
6. Install the air filter frame onto
the air filter and install the
assembly in the case.
7. Install the air filter case cover
and panel.
EC000082
cC
8Make sure the air filter is prop-
erly seated in the air filter
case.
8The engine should never be
run without the air filter
installed. Excessive piston
and/or cylinder wear may
result.
Air filter case drain hose cleaning
Frequently check the hose at the
bottom of the air filter case. If dirt
or water is visible, remove and
clean the hose, then reinstall it.
1. Hose
Recommended oil:
Engine oil
1
21
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EAU00629Carburetor adjustment
The carburetor is a vital part of the
engine and requires very sophisti-
cated adjustment. Most adjust-
ments should be left to a Yamaha
dealer who has the professional
knowledge and experience to do
so. However, the following may be
serviced by the owner as part of
routine maintenance.
EC000094
cC
The carburetor was set at the
Yamaha factory after many tests. If
the settings are changed, poor
engine performance and damage
may result.
EAU01168Idle speed adjustment
NOTE:
A diagnostic tachometer must be
used for this procedure.
1. Attach the tachometer. Start
the engine and warm it up for
a few minutes at approximate-
ly 1,000 to 2,000 r/min.
Occasionally rev the engine to
4,000 to 5,000 r/min. The
engine is warm when it quickly
responds to the throttle.2. Set the idle to the specified
engine speed by adjusting the
throttle stop screw. Turn the
screw in direction ato
increase engine speed and in
direction bto decrease engine
speed.
NOTE:
If the specified idle speed cannot
be obtained by performing the
above adjustment, consult a
Yamaha dealer.
1. Throttle stop screw
1
ab
Standard idle speed:
1,300 ~ 1,500 r/min
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