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5-4
OPERATION AND IMPORTANT RIDING POINTS
1
2
3
4
5
6
7
8
9
EAU01258Starting a warm engine
The starter (choke) is not required
when the engine is warm.
EC000046
cC
See the “Engine break-in” section
prior to operating the motorcycle
for the first time.
EC000048
cC
8Do not coast for long periods
with the engine off, and do
not tow the motorcycle a long
distance. Even with gears in
neutral, the transmission is
only properly lubricated when
the engine is running.
Inadequate lubrication may
damage the transmission.
8Always use the clutch when
changing gears. The engine,
transmission, and driveline are
not designed to withstand the
shock of forced shifting and
can be damaged by shifting
without using the clutch.
1
N5
4
3
2
1
EAU00423Shifting
The transmission lets you control
the amount of power you have
available at a given speed for start-
ing, accelerating, climbing hills,
etc. The use of the shift pedal is
shown in the illustration.
To shift into neutral, depress the
shift pedal repeatedly until it reach-
es the end of its travel, then raise
the pedal slightly.
1. Shift pedal
N. Neutral
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5-5
OPERATION AND IMPORTANT RIDING POINTS
1
2
3
4
5
6
7
8
9
EAU00424Tips for reducing fuel
consumption
Your motorcycle’s fuel consump-
tion depends to a large extent on
your riding style. The following
tips can help reduce fuel consump-
tion:
8Warm up the engine before
riding.
8Turn off the starter (choke) as
soon as possible.
8Shift up swiftly and avoid high
engine speeds during accelera-
tion.
8Do not double-clutch or rev the
engine while shifting down
and avoid high engine speeds
with no load on the engine.
8Turn off the engine instead of
letting it idle for an extended
length of time, i.e. in traffic
jams, at traffic lights or rail-
road crossings.
EAU01128Engine break-in
There is never a more important
period in the life of your motorcy-
cle than the period between zero
and 1,600 km. For this reason we
ask that you carefully read the fol-
lowing material. Because the
engine is brand new, you must not
put an excessive load on it for the
first 1,600 km. The various parts in
the engine wear and polish them-
selves to the correct operating
clearances. During this period, pro-
longed full throttle operation, or
any condition which might result in
excessive heating of the engine,
must be avoided.
EAU015000 ~ 1,000 km
Avoid operation above 1/3 throttle.
1,000 ~ 1,600 km
Avoid cruising speeds in excess of
1/2 throttle.
EC000057
cC
After 1,000 km of operation, be
sure to replace the engine oil and
clean the oil filter element and oil
strainer.
1,600 km and beyond
Proceed with normal riding.
EC000049
cC
If any engine trouble should occur
during the break-in period, consult
a Yamaha dealer immediately.
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6-3
PERIODIC MAINTENANCE AND MINOR REPAIR
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2
3
4
5
6
7
8
9
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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6-12
PERIODIC MAINTENANCE AND MINOR REPAIR
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8
9
1
2
2
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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8
9 If the specified free play cannot be
obtained, proceed with the follow-
ing steps.
4. Loosen the locknut at the
clutch lever.
5. Turn the adjusting bolt at the
clutch lever in direction ato
loosen the cable.
6. Loosen the locknut at the
crankcase side.
7. Turn the adjusting nut at the
crankcase in direction ato
increase free play or in direc-
tion bto decrease free play.
8. Tighten the locknut at the
crankcase and the clutch lever.
1. Locknut
2. Adjusting nut
EAU00694Clutch lever free play
adjustment
The clutch lever free play should
be adjusted to 10 ~ 15 mm.
1. Loosen the locknut at the
clutch lever.
2. Turn the adjusting bolt at the
clutch lever in direction ato
increase free play or in direc-
tion bto decrease free play.
3. Tighten the locknut at the
clutch lever.
1. Locknut
2. Adjusting bolt
c. Free play
EAU00696
Front brake lever free play
adjustment
The free play at the front brake
lever should be 2 ~ 5 mm.
1. Loosen the locknut.
2. Turn the adjusting bolt in
direction ato increase free
play or in direction bto
decrease free play.
3. After adjusting, tighten the
locknut.
1. Locknut
2. Adjusting bolt
c. Free play
c1
2
a
b
1
ab
2
12c
a b
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6-27
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
5
6
7
8
9
EAU02984Brake and shift pedal
lubrication
Lubricate the pivoting parts.
EAU02985Brake and clutch lever
lubrication
Lubricate the pivoting parts.
EAU02986Sidestand lubrication
Lubricate the sidestand pivoting
point and metal-to-metal contact
surfaces. Check that the sidestand
moves up and down smoothly.
EW000113
w
If the sidestand does not move
smoothly, consult a Yamaha deal-
er.
Recommended lubricant:
Engine oilRecommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
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8-1
EAU01038
SPECIFICATIONS
1
2
3
4
5
6
7
8
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
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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Fuel
Type Regular unleaded gasoline
Fuel tank capacity 7.0 L
Reserve amount 1.0 L
Carburetor
Type/quantity Y24P/1
Manufacturer TEIKEI
Spark plug
Manufacturer / Type NGK / DR8EA
Spark plug 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 50/14 (3.571)
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
Frame type Pressed and steel tube frame
Caster angle 26°
Trail 95 mm
Tires
Type With tube
Front
Size 130/80-18 66P
Manufacturer/ BRIDGESTONE / TW31
model
Rear
Size 180/80-14M/C 78P
Manufacturer/ BRIDGESTONE / TW34
model
Maximum load* 180 kg
Air pressure (cold tire)
up to 80 kg load*
SPECIFICATIONS
1
2
3
4
5
6
7
8
9
8-2
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