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3-6
To install the fuel tank cap
1. Insert the fuel tank cap into the
tank opening with the key insert-
ed in the lock, and then turn the
cap 1/3 turn clockwise.
2. Turn the key 1/3 turn clockwise,
and then remove it.
NOTE:
The fuel tank cap cannot be installed
unless the key is in the lock. In addi-
tion, the key cannot be removed if the
cap is not properly installed and
locked.
EW000023
w
Make sure that the fuel tank cap is
properly closed and locked before
riding.
INSTRUMENT AND CONTROL FUNCTIONS
3
EAU03753
Fuel
Make sure that there is sufficient fuel
in the tank. Fill the fuel tank to the
bottom of the filler tube as shown.
EW000130
w
8Do not overfill the fuel tank,
otherwise it may overflow
when the fuel warms up and
expands.
8Avoid spilling fuel on the hot
engine.
1
2
1. Filler tube
2. Fuel level
EAU00185
cC
Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since
fuel may deteriorate painted sur-
faces or plastic parts.
EAU04284
Recommended fuel:
REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity:
Total amount:
7.0 L
Reserve amount:
1.7 L
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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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