2002 YAMAHA TW125 check engine light

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TABLE OF CONTENTS
GIVE SAFETY THE RIGHT OF WAY ............... 1-1
DESCRIPTION ................................................. 2-1
Left view ......................................................... 2-1
Right view ...................................................... 2-2
Controls and instruments ............................... 2-3
INSTRUMENT AND CONTROL FUNCTIONS . 3-1
Main switch .................................................... 3-1
Indicator lights ................................................ 3-1
Speedometer unit .......................................... 3-2
Handlebar switches ........................................ 3-2
Clutch lever .................................................... 3-4
Shift pedal ...................................................... 3-4
Brake lever ..................................................... 3-4
Brake pedal .................................................... 3-5
Fuel tank cap ................................................. 3-5
Fuel ................................................................ 3-6
Fuel cock ........................................................ 3-7
Starter (choke) knob ...................................... 3-8
Steering lock .................................................. 3-8
Seat ................................................................ 3-9
Helmet holder ................................................. 3-9
Shock absorber ............................................ 3-10
Carrier .......................................................... 3-10
Luggage strap holders ................................. 3-10
Sidestand ..................................................... 3-11Ignition circuit cut-off system ........................ 3-11
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 .................................. 5-2
Shifting ........................................................... 5-3
Recommended shift points
(for Switzerland only) .................................. 5-3
Tips for reducing fuel consumption ................ 5-4
Engine break-in .............................................. 5-4
Parking ........................................................... 5-5
PERIODIC MAINTENANCE AND MINOR
REPAIR ............................................................. 6-1
Owner’s tool kit .............................................. 6-1
Periodic maintenance and lubrication chart ... 6-2
Removing and installing panels ..................... 6-5
Checking the spark plug ................................ 6-7
Engine oil and oil filter element ...................... 6-9
Cleaning the air filter element and check
hose .......................................................... 6-12
Adjusting the carburetor ............................... 6-14
Adjusting the engine idling speed ................ 6-14
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3-8
INSTRUMENT AND CONTROL FUNCTIONS
3
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Starter (choke) knob“1”Starting a cold engine requires a rich-
er air-fuel mixture, which is supplied
by the starter (choke).
Move the knob in direction ato turn
on the starter (choke).
Move the knob in direction bto turn
off the starter (choke).
a
b
1
1. Starter (choke) knob “1”
4. Check that the steering is locked,
remove the key, and then close
the lock cover.
To unlock the steering
1. Open the steering lock cover,
and then insert the steering lock
key.
2. Push the key in, turn it 1/8 turn
counterclockwise so that it
moves out, and then release it.
3. Remove the key, and then close
the lock cover.
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Steering lockSteering lockTo lock the steering
1. Turn the handlebar all the way to
right.
2. Open the steering lock cover,
and then insert the steering lock
key.
3. Turn the key 1/8 turn counter-
clockwise, push it in while turning
the handlebar slightly to the left,
and then turn the key 1/8 turn
clockwise.
21
1. Steering lock cover
2. Steering lock
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5-1
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OPERATION AND IMPORTANT RIDING POINTS
5
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w8Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer
regarding any control or func-
tion that you do not thorough-
ly understand.
8Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
8Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.
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Starting the engineIn order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
8The transmission is in the neutral
position.
8The transmission is in gear with
the clutch lever pulled and the
sidestand up.
EW000054
w8Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-12.
8Never ride with the sidestand
down.
1. Turn the fuel cock lever to “ON”.
2. Turn the key to “ON” and make
sure that the engine stop switch
is set to “#”.
3. Shift the transmission into the
neutral position.NOTE:
When the transmission is in the neu-
tral position, the neutral indicator light
should be on, otherwise have a
Yamaha dealer check the electrical
circuit.
ON
FUEL
RES
OFF
1
ON
1. Arrow mark positioned over “ON”
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5-4
OPERATION AND IMPORTANT RIDING POINTS
5
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Tips for reducing fuel
consumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Thoroughly warm up the engine.
8Turn the starter (choke) off as
soon as possible.
8Shift up swiftly, and avoid high
engine speeds during accelera-
tion.
8Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the
engine.
8Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad cross-
ings).
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Engine break-inThere is never a more important peri-
od in the life of your engine than the
period between 0 and 1,000 km. For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do
not put an excessive load on it for the
first 1,000 km. The various parts in
the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheat-
ing must be avoided.
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0–500 km
Avoid prolonged operation above 1/3
throttle.
500–1,000 km
Avoid prolonged operation above 1/2
throttle.
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cCAfter 1,000 km of operation, the
engine oil must be changed, and
the oil filter element and the oil
strainer cleaned.1,000 km and beyond
The vehicle can now be operated
normally.
EC000049
cCIf any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealer
check the vehicle.
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6-4
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake service
9Regularly check and, if necessary, correct the brake fluid level.
9Every two years replace the internal components of the brake master cylinder and caliper, and change the brake
fluid.
9Replace the brake hoses every four years and if cracked or damaged.21
*Carburetor•Check starter (choke) operation.
•Adjust engine idling speed.√√√√√ √
22 Engine oil•Change.
•Check oil level and vehicle for oil leakage.√√√√√ √
23 Engine oil filter element•Clean.√√√
24*Engine oil strainer•Clean.√
25*Front and rear brake
switches•Check operation.√√√√√ √
26 Moving parts and cables•Lubricate.√√√√ √
27*Lights, signals and
switches•Check operation.
•Adjust headlight beam.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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6-8
PERIODIC MAINTENANCE AND MINOR REPAIR
6To install the spark plug
1. Measure the spark plug gap with
a wire thickness gauge and, if
necessary, adjust the gap to
specification.
2. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then
tighten it to the specified torque.
a
a. Spark plug gap
NOTE:
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4-
1/2 turn past finger tight. However,
the spark plug should be tightened to
the specified torque as soon as pos-
sible.4. Install the spark plug cap.
Spark plug gap:
0.6–0.7 mmTightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf)
To check the spark plug
1. Check that the porcelain insula-
tor around the center electrode
of the spark plug is a medium-to-
light tan (the ideal color when the
motorcycle is ridden normally).NOTE:
If the spark plug shows a distinctly
different color, the engine could be
defective. Do not attempt to diagnose
such problems yourself. Instead,
have a Yamaha dealer check the
motorcycle.2. Check the spark plug for elec-
trode erosion and excessive car-
bon or other deposits, and
replace it if necessary.
Specified spark plug:
DR8EA (NGK)
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6-9
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Engine oil and oil filter
elementThe engine oil level should be
checked before each ride. In addition,
the oil must be changed and the oil
filter element cleaned at the intervals
specified in the periodic maintenance
and lubrication chart.
To check the engine oil level
1. Place the motorcycle on a level
surface and hold it in an upright
position.NOTE:
Make sure that the motorcycle is
positioned straight up when checking
the oil level. A slight tilt to the side
can result in a false reading.2. Start the engine, warm it up for
several minutes, and then turn it
off.3. Wait a few minutes until the oil
settles, and then check the oil
level through the check window
located at the bottom-right side
of the crankcase.
NOTE:
The engine oil should be between the
minimum and maximum level marks.4. If the engine oil is below the
minimum level mark, add suffi-
cient oil of the recommended
type to raise it to the correct
level.
2
3 1
1. Engine oil level check window
2. Maximum level mark
3. Minimum level mark
To change the engine oil (with or
without oil filter element cleaning)
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the
engine to collect the used oil.
3. Remove the engine oil filler cap
and drain bolt to drain the oil
from the crankcase.
1
1. Engine oil filler cap
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6-26
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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To adjust the drive chain slack
1. Loosen the brake pedal free play
adjusting nut.
2. Loosen the axle nut.
3. To tighten the drive chain, turn
the adjusting plate on each side
of the swingarm in direction a.
To loosen the drive chain, turn
the adjusting plate on each side
of the swingarm in direction b,
and then push the rear wheel for-
ward.
NOTE:
Make sure that both adjusting plates
are in the same position for proper
wheel alignment.
EC000096
cCImproper drive chain slack will
overload the engine as well as
other vital parts of the motorcycle
and can lead to chain slippage or
breakage. To prevent this from
occurring, keep the drive chain
slack within the specified limits.4. Tighten the axle nut to the speci-
fied torque.5. Adjust the brake pedal free play.
(See page 6-21 for brake pedal
free play adjustment proce-
dures.)
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wAfter adjusting the brake pedal
free play, check the operation of
the brake light.
32
a
b
1
1. Brake pedal free play adjusting nut
2. Axle nut
3. Drive chain adjusting plate
Tightening torque:
Axle nut:
90 Nm (9.0 m·kgf)
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