check engine YAMAHA DT125R 2002 Owners Manual

EAU00009
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 and warning lights ............................ 3-1
Speedometer unit .......................................... 3-2
Tachometer .................................................... 3-2
Coolant temperature gauge ............................ 3-3
Handlebar switches ........................................ 3-3
Clutch lever .................................................... 3-4
Shift pedal ...................................................... 3-4
Brake lever ..................................................... 3-5
Brake pedal .................................................... 3-5
Fuel tank cap .................................................. 3-5
Fuel (except for Switzerland and Austria) ...... 3-6
Fuel (for Switzerland and Austria) ................. 3-6
Catalytic converter
(for Switzerland and Austria) ....................... 3-7
2-stroke engine oil .......................................... 3-8
Fuel cock ........................................................ 3-9
Starter (choke) lever ..................................... 3-10Kickstarter .................................................... 3-10
Steering lock ................................................. 3-10
Seat .............................................................. 3-11
Helmet holder ............................................... 3-12
Adjusting the shock absorber assembly ....... 3-12
Carrier .......................................................... 3-14
YEIS handling precautions .......................... 3-14
YPVS ............................................................ 3-14
Sidestand ..................................................... 3-15
Ignition circuit cut-off system ........................ 3-16
PRE-OPERATION CHECKS ............................. 4-1
Pre-operation check list .................................. 4-1
OPERATION AND IMPORTANT
RIDING POINTS ............................................... 5-1
Starting a cold engine .................................... 5-1
Starting a warm engine .................................. 5-2
Shifting ........................................................... 5-2
Recommended shift points
(for Switzerland only) .................................. 5-3
Tips for reducing fuel consumption ................ 5-3
Engine break-in .............................................. 5-4
Parking ........................................................... 5-5
123
45
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PERIODIC MAINTENANCE AND
MINOR REPAIR ................................................ 6-1
Owner’s tool kit ............................................... 6-1
Periodic maintenance and lubrication chart ... 6-2
Removing and installing cowlings .................. 6-5
Removing and installing panels ...................... 6-7
Checking the spark plug ................................. 6-9
Transmission oil ........................................... 6-10
Coolant ......................................................... 6-12
Changing the coolant ................................... 6-14
Cleaning the air filter element........................ 6-16
Adjusting the carburetor ............................... 6-17
Adjusting the engine idling speed ................ 6-17
Adjusting the throttle cable free play ............ 6-18
Tires ............................................................. 6-19
Spoke wheels ............................................... 6-21
Adjusting the clutch lever free play ............... 6-22
Adjusting the brake lever free play ............... 6-23
Adjusting the brake pedal position ............... 6-23
Adjusting the rear brake light switch ............. 6-24
Checking the front and rear brake pads ....... 6-24
Checking the brake fluid level ...................... 6-25
Changing the brake fluid .............................. 6-26
Drive chain slack .......................................... 6-27
Lubricating the drive chain ........................... 6-28
Checking and lubricating the cables ............. 6-29Checking and lubricating the
throttle grip and cable ................................ 6-29
Adjusting the Autolube pump ....................... 6-30
Checking and lubricating the brake and
shift pedals ................................................ 6-30
Checking and lubricating the brake and
clutch levers .............................................. 6-30
Checking and lubricating the sidestand ....... 6-31
Checking the front fork ................................. 6-31
Checking the steering ................................... 6-32
Checking the wheel bearings ....................... 6-32
Battery .......................................................... 6-33
Replacing the fuse ....................................... 6-35
Replacing the headlight bulb ........................ 6-36
Replacing a turn signal light bulb ................. 6-37
Replacing the tail/brake light bulb ................ 6-38
Supporting the motorcycle ............................ 6-39
Front wheel ................................................... 6-39
Rear wheel ................................................... 6-42
Troubleshooting ............................................ 6-43
Troubleshooting charts ................................. 6-44
MOTORCYCLE CARE AND STORAGE ........... 7-1
Care ................................................................ 7-1
Storage ........................................................... 7-4
TABLE OF CONTENTS6
7
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3-1
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INSTRUMENT AND CONTROL FUNCTIONS
3
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Main switchThe main switch controls the ignition
and lighting systems. The various
main switch positions are described
below.
EAU00036
ON
All electrical systems are supplied
with power, and the engine can be
started. The key cannot be removed.
EAU00038
OFF
All electrical systems are off. The key
can be removed.
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Neutral indicator light “N”
This indicator light comes on when
the transmission is in the neutral
position.
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2-stroke engine oil level warning
light “
7
”
This warning light comes on when
the 2-stroke engine oil level is low.
The electrical circuit of the warning
light can be checked according to the
following procedure.
1. Turn the key to “ON”.
2. Shift the transmission into the
neutral position.
3. If the warning light does not
come on, have a Yamaha dealer
check the electrical circuit.
NOTE:
Even if the 2-stroke engine oil level is
sufficient, the warning light may flick-
er when riding on a slope or during
sudden acceleration or deceleration,
but this is not a malfunction.
ON
OFF
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Indicator and warning lights
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Turn signal indicator light “5”
This indicator light flashes when the
turn signal switch is pushed to the left
or right.
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High beam indicator light “&”
This indicator light comes on when
the high beam of the headlight is
switched on.
1
2
3
4
1. Turn signal indicator light “5”
2. High beam indicator light “&”
3. Neutral indicator light “N”
4. 2-stroke engine oil level warning
light “
7
”
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3-10
INSTRUMENT AND CONTROL FUNCTIONS
3
EAU03839
Starter (choke) lever“1”Starting a cold engine requires a rich-
er air-fuel mixture, which is supplied
by the starter (choke).
Move the lever in direction ato turn
on the starter (choke).
Move the lever in direction bto turn
off the starter (choke).
a
b
1
1. Starter (choke) lever “1”
EAU00212
KickstarterTo start the engine, fold out the kick-
starter lever, move it down lightly with
your foot until the gears engage, and
then push it down smoothly but force-
fully. This model is equipped with a
primary kickstarter, allowing the
engine to be started in any gear if the
clutch is disengaged. However, shift-
ing the transmission into the neutral
position before starting is recom-
mended.
1
1. Kickstarter
EAU02934
Steering lockTo lock the steering
1. Turn the handlebar all the way to
the right.
2. Open the steering lock cover,
and then insert the 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.
4. Check that the steering is locked,
remove the key, and then close
the lock cover.
2
1
1. Steering lock cover
2. Steering lock
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3-15
INSTRUMENT AND CONTROL FUNCTIONS
3
EC000023
cCThe YPVS has been set and exten-
sively tested at the Yamaha facto-
ry. Changing these settings with-
out sufficient technical knowledge
may result in poor performance of
or damage to the engine.YPVS operation noises can be heard
in the following instances:
8When the key is turned to “ON”
and the engine is started.
8When the engine stalls with the
key in the “ON” position.
EC000024
cCIf the YPVS does not operate, have
a Yamaha dealer check it.
EAU00330
SidestandThe sidestand is located on the left
side of the frame. Raise the side-
stand or lower it with your foot while
holding the motorcycle upright.NOTE:
The built-in sidestand switch is part of
the ignition circuit cut-off system,
which cuts the ignition in certain situ-
ations. (See further down for an
explanation of the ignition circuit cut-
off system.)
EW000044
wThe motorcycle must not be ridden
with the sidestand down, or if the
sidestand cannot be properly
moved up (or does not stay up),
otherwise the sidestand could con-
tact the ground and distract the
operator, resulting in a possible
loss of control. Yamaha’s ignition
circuit cut-off system has been
designed to assist the operator in
fulfilling the responsibility of rais-
ing the sidestand before starting
off. Therefore, check this system
regularly as described below and
have a Yamaha dealer repair it if it
does not function properly.
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3-16
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Ignition circuit cut-off
systemThe ignition circuit cut-off system
(comprising the sidestand switch and
neutral switch) has the following func-
tions.
8It prevents starting when the
transmission is in gear and the
sidestand is still down.
8It cuts the running engine when
the transmission is in gear and
the sidestand is moved down.
Periodically check the operation of
the ignition circuit cut-off system
according to the following procedure.
EW000045
wIf a malfunction is noted, have a
Yamaha dealer check the system
before riding.INSTRUMENT AND CONTROL FUNCTIONS
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3-17
INSTRUMENT AND CONTROL FUNCTIONS
3
With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is set to “
#”.
3. Turn the key to “ON”.
4. Shift the transmission into the neutral position.
5. Push the kickstarter lever down.
Does the engine start?
The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
The sidestand switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
NO
NOTE:This check is most reliable if performed with
a warmed-up engine.
YESYES NO
The system is OK. The motorcycle can be ridden.
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4-1
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PRE-OPERATION CHECKS
4The condition of a vehicle is the owner’s responsibility. Vital components can start to deteriorate quickly and unexpect-
edly, even if the vehicle remains unused (for example, as a result of exposure to the elements). Any damage, fluid leak-
age or loss of tire air pressure could have serious consequences. Therefore, it is very important, in addition to a thor-
ough visual inspection, to check the following points before each ride.
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Pre-operation check list
ITEM CHECKS PAGE
Fuel•Check fuel level in fuel tank.
•Refuel if necessary.
•Check fuel line for leakage.3-5–3-7
2-stroke engine oil•Check oil level in oil tank.
•If necessary, add recommended oil to specified level.
•Check vehicle for oil leakage.3-8
Transmission oil•Check oil level in transmission case.
•If necessary, add recommended oil to specified level.6-10–6-12
Coolant•Check coolant level in reservoir.
•If necessary, add recommended coolant to specified level.
•Check cooling system for leakage.6-12–6-15
Front brake•Check operation.
•If soft or spongy, have Yamaha dealer bleed hydraulic system.
•Check lever free play.
•Adjust if necessary.
•Check fluid level in reservoir.
•If necessary, add recommended brake fluid to specified level.
•Check hydraulic system for leakage.3-5, 6-23, 6-24–6-26
Rear brake•Check operation.
•If soft or spongy, have Yamaha dealer bleed hydraulic system.
•Check fluid level in reservoir.
•If necessary, add recommended brake fluid to specified level.
•Check hydraulic system for leakage.3-5, 6-23–6-26
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5-1
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OPERATION AND IMPORTANT RIDING POINTS
5
EAU00373
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.
EAU01177
Starting a cold 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 3-17.
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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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
8Avoid prolonged operation above
6,000 r/min.
8After every hour of operation,
stop the engine, and then let it
cool for five to ten minutes.
8Vary the engine speed from time
to time. Do not operate the
engine at one set throttle posi-
tion.
500–1,000 km
8Avoid prolonged operation above
7,000 r/min.
8Rev the engine freely through
the gears, but do not use full
throttle at any time.
EC000060
cCAfter 1,000 km of operation, the
transmission oil must be changed.
1,000 km and beyond
The vehicle can now be operated
normally.
EC000053
cC8Keep the engine speed out of
the tachometer red zone.
8If any engine trouble should
occur during the engine break-
in period, immediately have a
Yamaha dealer check the vehi-
cle.
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