2003 YAMAHA TW125 air filter

6-13
PERIODIC MAINTENANCE AND MINOR REPAIR
63. 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
cC
8Make 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 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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8-1
EAU01038
SPECIFICATIONS
8
SpecificationsSpecifications
Model TW125
Dimensions
Overall length 2,135 mm
Overall width 820 mm
Overall height 1,120 mm
Seat height 820 mm
Wheelbase 1,350 mm
Ground clearance 255 mm
Minimum turning radius 2,100 mm
Basic weight (with oil and full
fuel tank)127 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
cC
In order to prevent clutch slippage (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 CONSERVING II” or higher.
Capacity
Without oil filter element
removal 1.0 L
With oil filter element removal 1.1 L
Total amount (dry engine) 1.3 L
–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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8-2
SPECIFICATIONS
8
Air filterWet type element
Fuel
Type REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity 7.0 L
Reserve amount 1.7 L
Carburetor
Manufacturer TEIKEI
Model ×quantity MV28 ×1
Spark plug
Manufacturer/Type NGK/DR8EA
Gap 0.6–0.7 mm
Clutch typeWet, multiple-disc
Transmission
Primary reduction system Spur gear
Primary reduction ratio 74/20 (3.700)
Secondary reduction system Chain drive
Secondary reduction ratio 3.643
Number of drive chain
sprocket teeth (rear/front) 51/14
Transmission type Constant mesh 5-speed
Operation Left foot operationGear ratio 1st 2.250
2nd 1.476
3rd 1.125
4th 0.926
5th 0.793
Chassis
Frame type Diamond
Caster angle 25.83°
Trail 93 mm
Tires
Front
Type With tube
Size 130/80-18 M/C 66P
Manufacturer/ BRIDGESTONE/TW-203
model
Rear
Type With tube
Size 180/80-14 M/C 78P
Manufacturer/ BRIDGESTONE/TW-204
model
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