2002 YAMAHA DT125R engine

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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2-2
DESCRIPTION
2
11. Owner’s tool kit (page 6-1)
12. Fuse (page 6-35)
13. Battery (page 6-33)
14. 2-stroke engine oil tank (page 3-8)
15. Brake pedal (page 3-5, 6-23)16. Shock absorber spring
preload adjusting nut (page 3-12)
11 12 14
15 1613
Right view
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3-1
EAU00027
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
EAU00057
Turn signal indicator light “5”
This indicator light flashes when the
turn signal switch is pushed to the left
or right.
EAU00063
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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3-2
EAU01087
Speedometer unit The speedometer unit is equipped
with a speedometer, an odometer
and a tripmeter. The speedometer
shows riding speed. The odometer
shows the total distance traveled.
The tripmeter shows the distance
traveled since it was last set to zero
with the reset knob. The tripmeter
can be used to estimate the distance
that can be traveled with a full tank of
fuel. This information will enable you
to plan future fuel stops.
NOTE:
Only for the German model equipped
with a speed limiter:
The speed limiter prevents the motor-
cycle from exceeding a riding speed
of 80 km/h.
INSTRUMENT AND CONTROL FUNCTIONS
3
4
2
3
1
1. Speedometer unit
2. Odometer
3. Tripmeter
4. Reset knob
EAU00102
TachometerThe tachometer allows the rider to
monitor the engine speed and keep it
within the ideal power range.
EC000003
cCDo not operate the engine in the
tachometer red zone.
Red zone: 10,500 r/min and above
1
2
1. Tachometer
2. Red zone
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3-3
INSTRUMENT AND CONTROL FUNCTIONS
3
EAU01652
Coolant temperature gaugeWith the key in the “ON” position, the
coolant temperature gauge indicates
the temperature of the coolant. The
coolant temperature varies with
changes in the weather and engine
load. If the needle reaches or enters
the red zone, stop the motorcycle
and let the engine cool. (See page
6-45 for further instructions.)
EC000002
cCDo not operate the engine if it is
overheated.
EAU03889
Turn signal switch “4/6”
To signal a right-hand turn, push this
switch to “6”. To signal a left-hand
turn, push this switch to “4”. When
released, the switch returns to the
center position. To cancel the turn
signal lights, push the switch in after
it has returned to the center position.
EAU00129
Horn switch “*”
Press this switch to sound the horn.
1
2
1. Coolant temperature gauge
2. Red zone
EAU00118
Handlebar switches
EAU03898
Light switch “9/
'
/:”
Set this switch to “'
” to turn on
the auxiliary light, meter lighting and
taillight. Set the switch to “:” to turn
on the headlight also. Set the switch
to “9” to turn off all the lights.
EAU03888
Dimmer switch “&/%”
Set this switch to “&” for the high
beam and to “%” for the low beam.
2
1
3
4
1. Light switch “9/
'
/:”
2. Dimmer switch “&/%”
3. Turn signal switch “4/6”
4. Horn switch “*”
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3-4
EAU03890
Engine stop switch “#/$”
Set this switch to “#” before starting
the engine. Set this switch to “$” to
stop the engine in case of an emer-
gency, such as when the motorcycle
overturns or when the throttle cable is
stuck.INSTRUMENT AND CONTROL FUNCTIONS
3
1
1. Engine stop switch “#/$”
EAU00155
Clutch leverThe clutch lever is located at the left
handlebar grip. To disengage the
clutch, pull the lever toward the han-
dlebar grip. To engage the clutch,
release the lever. The lever should
be pulled rapidly and released slowly
for smooth clutch operation.
1
1. Clutch lever
EAU00157
Shift pedalThe shift pedal is located on the left
side of the engine and is used in
combination with the clutch lever
when shifting the gears of the
6-speed constant-mesh transmission
equipped on this motorcycle.
1
1. Shift pedal
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3-6
INSTRUMENT AND CONTROL FUNCTIONS
3To install the fuel tank cap
1. Insert the fuel tank cap into the
tank opening with the key insert-
ed in the lock, and then turn the
cap 1/3 turn clockwise.
2. Turn the key 1/4 turn clockwise,
and then remove it.
NOTE:
The fuel tank cap cannot be installed
unless the key is in the lock. In addi-
tion, the key cannot be removed if the
cap is not properly installed and
locked.
EW000023
wMake sure that the fuel tank cap is
properly closed and locked before
riding.
EAU03753
Fuel(except for Switzerland and
Austria)
Make sure that there is sufficient fuel
in the tank. Fill the fuel tank to the
bottom of the filler tube as shown.
EW000130
w8Do not overfill the fuel tank,
otherwise it may overflow
when the fuel warms up and
expands.
8Avoid spilling fuel on the hot
engine.
21
1. Filler tube
2. Fuel level
EAU03754
Fuel(for Switzerland and Austria)
Make sure that there is sufficient fuel
in the tank. When refueling, be sure
to insert the pump nozzle into the fuel
tank filler hole and to fill the tank to
the bottom of the filler tube as shown.
1
3
5 42
1. Pump nozzle
2. Fuel tank filler hole
3. Filler tube
4. Fuel level
5. Leaf valve
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