
EAU00009
TABLE OF CONTENTS
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GIVE SAFETY THE RIGHT OF WAY ..................1-1
DESCRIPTION .....................................................2-1
Left view............................................................2-1
Right view .........................................................2-2
Controls/Instruments .......................................2-3
INSTRUMENT AND CONTROL
FUNCTIONS ........................................................3-1
Main switch ......................................................3-1
Indicator lights..................................................3-1
Speedometer ....................................................3-2
Handlebar switches..........................................3-2
Clutch lever .......................................................3-4
Shift pedal.........................................................3-4
Front brake lever ..............................................3-4
Rear brake pedal ..............................................3-5
Fuel tank cap.....................................................3-5
Fuel ....................................................................3-6
Fuel cock ...........................................................3-7
Starter (choke) “1” .........................................3-8
Steering lock .....................................................3-8
Seat ...................................................................3-9
Helmet holder ...................................................3-9
Rear shock absorber ......................................3-10
Rear carrier .....................................................3-10
Luggage strap holders ...................................3-10Sidestand ........................................................3-11
Sidestand/clutch switch operation check .....3-12
PRE-OPERATION CHECKS.................................4-1
Pre-operation check list ...................................4-1
OPERATION AND IMPORTANT RIDING
POINTS................................................................5-1
Starting the engine ..........................................5-1
Starting a warm engine ...................................5-4
Shifting..............................................................5-4
Tips for reducing fuel consumption ...............5-5
Engine break-in ................................................5-5
Parking ..............................................................5-6
PERIODIC MAINTENANCE AND MINOR
REPAIR ................................................................6-1
Tool kit ..............................................................6-1
Periodic maintenance and lubrication............6-3
Cowling and panel removal and
installation ........................................................6-6
Panel A ..............................................................6-6
Panel B ..............................................................6-7
Cowling C..........................................................6-8
Spark plug.........................................................6-8
Engine oil ..........................................................6-9
Air filter ...........................................................6-121
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2-1
EAU00026
DESCRIPTION
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1. Fuel tank (page 3-5)
2. Fuel cock (page 3-7)
3. Helmet holder (page 3-9)
4. Luggage straps (page 3-10)5. Shift pedal (page 3-4)
6. Air filter (page 6-12)
7. Chain adjusting plates (page 6-24)
12 3 4
5
67Left view
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6-3
PERIODIC MAINTENANCE AND MINOR REPAIR
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EAU00473PERIODIC MAINTENANCE AND LUBRICATION
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)
1 * Fuel line 9Check fuel hoses for cracks or damage.
ÖÖ
9Replace if necessary.
2 Spark plug9Check condition.
ÖÖÖ
9Clean, regap or replace if necessary.
3 * Valves 9Check valve clearance.
ÖÖÖ
9Adjust if necessary.
4 Air filter9Clean or replace if necessary.ÖÖ
9Check electrolyte level and specific gravity.
5 * Battery9Correct or recharge if necessary.ÖÖ
9Make sure that the breather hose is properly routed.
6 Clutch9Check operation.
ÖÖÖ
9Adjust or replace cable.
9Check operation, fluid level and vehicle for fluid leakage.
7 * Front brake (See NOTE on page 6-5.)
ÖÖÖ
9Correct accordingly.
9Replace brake pads if necessary.
8 * Rear brake 9Check operation.
ÖÖÖ
9Adjust brake pedal freeplay and replace brake shoes if necessary.
9 * Wheels 9Check balance, runout, spoke tightness and for damage.
ÖÖ
9Tighten spokes and rebalance, replace if necessary.
9Check tread depth and for damage.
10 * Tires9Replace if necessary.
ÖÖ
9Check air pressure.
9Correct if necessary.
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6-5
PERIODIC MAINTENANCE AND MINOR REPAIR
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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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PERIODIC MAINTENANCE AND MINOR REPAIR
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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
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PERIODIC MAINTENANCE AND MINOR REPAIR
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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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PERIODIC MAINTENANCE AND MINOR REPAIR
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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
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8-1
EAU01038
SPECIFICATIONS
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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
cC
Be sure to use motor oils that do not contain anti-friction
modifiers. Passenger car motor oils (often labeled “Energy
Conserving”) contain anti-friction additives which will cause
clutch and/or starter clutch slippage, resulting in reduced
component life and poor engine performance.
Capacity
Periodic oil change 1.0 L
With oil filter replacement 1.1 L
Total amount 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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