check engine light 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
EAU00028
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.
EAU00061
Neutral indicator light “N”
This indicator light comes on when
the transmission is in the neutral
position.
EAU04258
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
EAU03034
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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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.
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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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 cylinders and calipers, 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*Autolube pump•Check operation.
•Bleed if necessary.√√√√
23 Transmission oil•Check oil level.√√√√√ √
•Change.√√
24*Cooling system•Check coolant level and vehicle for coolant leakage.√√√√ √
•Change.Every 3 years
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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6-9
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01833
Checking the spark plugThe spark plug is an important
engine component, which is easy to
check. Since heat and deposits will
cause any spark plug to slowly erode,
the spark plug should be removed
and checked in accordance with the
periodic maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
To remove the spark plug
1. Remove the spark plug cap.
1
1. Spark plug cap
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. 2. Remove the spark plug as
shown, with the spark plug
wrench included in the owner’s
tool kit.
1
1. Spark plug wrench
Specified spark plug:
BR9ES (NGK)
BR8ES (NGK) (CH, A only)
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6-10
PERIODIC MAINTENANCE AND MINOR REPAIR
6 To 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
EAU04272
Transmission oilThe transmission oil level should be
checked before each ride. In addition,
the transmission oil must be changed
at the intervals specified in the peri-
odic maintenance and lubrication
chart.
To check the transmission 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.
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 possible.4. Install the spark plug cap.
Spark plug gap:
0.7–0.8 mmTightening torque:
Spark plug:
20 Nm (2.0 m0kgf)
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6-12
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EC000077
cC8In order to prevent clutch slip-
page (since the transmission
oil also lubricates the clutch),
do not mix any chemical addi-
tives with the oil.
8Make sure that no foreign
material enters the transmis-
sion.6. Start the engine, and then let it
idle for several minutes while
checking the transmission for oil
leakage. If oil is leaking, immedi-
ately turn off the engine and
check for the cause.
EAU01808
CoolantTo check the coolant level
1. Place the motorcycle on a level
surface and hold it in an upright
position.NOTE:
8The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
8Make sure that the motorcycle is
positioned straight up when
checking the coolant level. A
slight tilt to the side can result in
a false reading.
2. Remove panel A. (See page 6-8
for panel removal and installation
procedures.)
3. Check the coolant level in the
coolant reservoir.NOTE:
The coolant should be between the
minimum and maximum level marks.
2
1
1. Maximum level mark
2. Minimum level mark
Recommended transmission oil:
See page 8-1.
Oil quantity:
Periodic oil change:
0.75 L
Total amount (dry transmission):
0.8 L
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