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95. 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.
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. Sponge material
2. Air filter element frame
Recommended oil:
Engine oil
1
2
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(s) and/or cylinder(s)
may become excessively
worn.8. Install the air filter case cover by
installing the screws.
9. Install the panel.
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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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EAU01038
SPECIFICATIONS
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9
Specifications
Model TW125
Dimensions
Overall length 2,140 mm
Overall width 810 mm
Overall height 1,120 mm
Seat height 805 mm
Wheelbase 1,330 mm
Ground clearance 260 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and full
fuel tank)125 kg
Engine
Engine type Air-cooled 4-stroke, SOHC
Cylinder arrangement Forward inclined
single cylinder
Displacement 124 cm
3
Bore ´Stroke 57.0 ´48.8 mm
Compression ratio 10:1
Starting system Electric starter
Lubrication system Wet sumpEngine oil
Type
Recommended engine oil
classification API Service SE, SF, SG type
or higher
cCBe sure to use motor oils that do not contain anti-friction
modifiers. Passenger car motor oils (often labeled ÒEnergy
ConservingÓ) contain anti-friction additives which will cause
clutch and/or starter clutch slippage, resulting in reduced
component life and poor engine performance.
Capacity
Without oil filter element
removal 1.0 L
With oil filter element removal 1.1 L
Total amount (dry engine) 1.3 L
Air filterWet type element
–10° 0° 10° 20° 30°
40°
SAE 10W/30
SAE 10W/40
SAE 20W/40
SAE 20W/50
–20°
SAE 15W/40 50°C
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