2000 YAMAHA DT125R transmission

PERIODIC MAINTENANCE AND MINOR
REPAIR................................................................6-1
Tool kit..............................................................6-1
Periodic maintenance and lubrication chart......6-3
Cowling removal and installation......................6-6
Cowling A..........................................................6-6
Cowling B..........................................................6-7
Cowling C.........................................................6-8
Panel removal and installation..........................6-8
Panel D.............................................................6-9
Panel E.............................................................6-9
Spark plug.......................................................6-10
Transmission oil..............................................6-11
Cooling system...............................................6-12
Changing the coolant......................................6-13
Air filter............................................................6-15
Carburetor adjustment....................................6-16
Idle speed adjustment.....................................6-17
Throttle cable free play adjustment.................6-17
Tires................................................................6-18
Wheels............................................................6-20
Clutch lever free play adjustment...................6-21
Front brake lever free play adjustment...........6-21
Rear brake pedal height adjustment...............6-22
Brake light switch adjustment.........................6-23
Checking the front and rear brake pads.........6-23Inspecting the brake fluid level.......................6-24
Brake fluid replacement..................................6-25
Drive chain slack check..................................6-25
Drive chain slack adjustment..........................6-26
Drive chain lubrication....................................6-26
Cable inspection and lubrication.....................6-27
Throttle cable and grip lubrication...................6-27
Autolube pump adjustment.............................6-28
Brake and shift pedal lubrication.....................6-28
Brake and clutch lever lubrication...................6-28
Sidestand lubrication......................................6-29
Front fork inspection.......................................6-29
Steering inspection.........................................6-30
Wheel bearings...............................................6-30
Battery............................................................6-31
Fuse replacement...........................................6-33
Headlight bulb replacement............................6-33
Turn signal light bulb replacement..................6-35
Tail/brake light bulb replacement....................6-35
Supporting the motorcycle..............................6-36
Front wheel removal.......................................6-36
Front wheel installation...................................6-37
Rear wheel removal........................................6-38
Rear wheel installation....................................6-39
Troubleshooting..............................................6-39
Troubleshooting chart.....................................6-40
TABLE OF CONTENTS
1
2
3
4
5
6
7
8
9
6
3MB-9-E7 12/27/00 2:52 PM Page 6

3-1
ON
OFF
EAU00028
Main switchThe main switch controls the ignition
and lighting systems. Its operation is
described below.
EAU00036
ON
Electrical circuits are switched on.
The engine can be started. The key
cannot be removed in this position.
EAU00038
OFF
All electrical circuits are switched off.
The key can be removed in this posi-
tion.EAU00027
INSTRUMENT AND CONTROL FUNCTIONS
1
23
4
5
6
7
8
9
EAU00063
High beam indicator light Ò
&Ó
This indicator comes on when the
headlight high beam is used.
EAU01313
Oil level indicator light Ò
7
Ó
This indicator comes on when the oil
level is low. This light circuit can be
checked by the procedure on page 3-
2.EC000000
cCDo not run the motorcycle until
you know it has sufficient engine
oil.NOTE
Even if the oil is filled to the specified
level, the indicator light may flicker
when riding on a slope or during sud-
den acceleration or deceleration, but
this is normal.
1
2
3
4
EAU00056
Indicator lights
EAU00057
Turn indicator light Ò5Ó
This indicator flashes when the turn
switch is moved to the left or right.
EAU00061
Neutral indicator light ÒNÓ
This indicator comes on when the
transmission is in neutral.1.Turn indicator light Ò5Ó
2.High beam indicator light Ò&Ó
3.Neutral indicator light ÒNÓ
4.Oil level indicator light Ò
7
Ó
3MB-9-E7 12/27/00 2:52 PM Page 13

EAU00075
Oil level indicator circuit check
3-2
INSTRUMENT AND CONTROL FUNCTIONS
1
23
4
5
6
7
8
9Turn the main switch to ÒONÓ.
Put the transmission in neutral.
Oil level indicator light
does not come on.Ask a Yamaha dealer to
inspect electrical circuit.
Oil level indicator light
comes on.
Oil level indicator light
does not come on.
Supply engine oil.
Shift into gear.
Engine oil level and
electrical circuit are OK.
Go ahead with riding.
Oil level indicator light
comes on.
3MB-9-E7 12/27/00 2:52 PM Page 14

3-5
INSTRUMENT AND CONTROL FUNCTIONS
1
23
4
5
6
7
8
9
1
1.Engine stop switch
EAU00138
Engine stop switch
The engine stop switch is a safety
device for use in an emergency such
as when the motorcycle overturns or
if trouble occurs in the throttle sys-
tem. Turn the switch to Ò#Ó to start
the engine. In case of emergency,
turn the switch to Ò$Ó to stop the
engine.
EAU00155
Clutch leverThe clutch lever is located on the left
handlebar. Pull the clutch lever to the
handlebar to disengage the clutch,
and release the lever to engage the
clutch. The lever should be pulled
rapidly and released slowly for
smooth clutch operation.
6
5
4
3
2
1 N
1
EAU00157
Shift pedalThis motorcycle is equipped with a
constant-mesh 6-speed transmission.
The shift pedal is located on the left
side of the engine and is used in
combination with the clutch when
shifting.1.Shift pedal
N.Neutral
1
1.Clutch lever
3MB-9-E7 12/27/00 2:52 PM Page 17

EW000045
wIf improper operation is noted,
consult a Yamaha dealer immedi-
ately.
3-16
INSTRUMENT AND CONTROL FUNCTIONS
1
23
4
5
6
7
8
9
ENGINE WILL STALL.SIDESTAND SWITCH IS OK.
EAU00333
Sidestand switch operation
checkCheck the operation of the sidestand
switch against the information below.TURN THE MAIN SWITCH TO ÒONÓ AND
THE ENGINE STOP SWITCH TO Ò#Ó.TRANSMISSION IS IN NEUTRAL AND
SIDESTAND IS DOWN.PULL IN THE CLUTCH LEVER AND
PUT TRANSMISSION IN GEAR.ENGINE WILL START.KICK THE KICK STARTER.
EW000044
wThis motorcycle must not be oper-
ated with the sidestand in the
down position. If the stand is not
properly retracted, it could contact
the ground and distract the opera-
tor, resulting in a possible loss of
control. Yamaha has designed into
this motorcycle a lockout system
to assist the operator in fulfilling
the responsibility of retracting the
sidestand. Please check carefully
the operating instructions listed
below and if there is any indication
of a malfunction, return the motor-
cycle to a Yamaha dealer immedi-
ately for repair.
3MB-9-E7 12/27/00 2:52 PM Page 28

4-1
EAU01114
PRE-OPERATION CHECKS
1
2
34
5
6
7
8
9 Owners are personally responsible for their vehicleÕs condition. Your motorcycleÕs vital functions can start to deteriorate
quickly and unexpectedly, even if it remains unused (for instance, if it is exposed to the elements). Any damage, fluid
leak or loss of tire pressure could have serious consequences. Therefore, it is very important that, in addition to a thor-
ough visual inspection, you check the following points before each ride.
EAU00340
PRE-OPERATION CHECK LIST
ITEMCHECKSPAGE
Front brake9Check operation, free play, fluid level and vehicle for fluid leakage.
9Fill with DOT 4 (or DOT 3) brake fluid if necessary.
3-6, 6-21 ~ 6-25
Rear brake9Check operation, free play, fluid level and vehicle for fluid leakage.
9Fill with DOT 4 (or DOT 3) brake fluid if necessary.
Clutch9Check operation, condition and free play.
3-5, 6-21
9Adjust if necessary.
9Check for smooth operation.
Throttle grip and housing9Lubricate.6-17, 6-27
9Adjust throttle cable free play if necessary.
Engine oil9Check oil level.
3-9
9Fill with oil if necessary.
Transmission oil9Check oil level.
6-11 ~ 6-12
9Fill with oil if necessary.
Coolant9Check coolant level.
6-12
9Fill with coolant if necessary.
Drive chain9Check chain slack and condition.
6-26 ~ 6-27
9Adjust if necessary.
Wheels and tires9Check tire pressure, wear, damage and spoke tightness.
6-18 ~ 6-20
9Tighten spokes if necessary.
Control and meter cable9Check for smooth operation.
6-27
9Lubricate if necessary.
3MB-9-E7 12/27/00 2:52 PM Page 29

5-1
1
2
3
45
6
7
8
9
EAU00373
w8 8
Before riding this motorcycle,
become thoroughly familiar
with all operating controls and
their functions. Consult a
Yamaha dealer regarding any
control or function that you do
not thoroughly understand.
8 8
Never start your engine or let
it run for any length of time in
a closed area. The exhaust
fumes are poisonous and can
cause loss of consciousness
and death within a short time.
Always operate your motorcy-
cle in an area with adequate
ventilation.
8 8
Before starting out, always be
sure the sidestand is up.
Failure to retract the sidestand
completely can result in a seri-
ous accident when you try to
turn a corner.
EAU01177
Starting the engineNOTE:
This motorcycle is equipped with an
ignition circuit cut-off system. The
engine can be started only under one
of the following conditions:
8The transmission is in neutral.
8The sidestand is up, the trans-
mission is in gear and the clutch
is disengaged.
The motorcycle must not be ridden
when the sidestand is down.
EW000056
wBefore going through the following
steps, check the function of the
sidestand switch. (Refer to page
3-16.)
EAU00372
OPERATION AND IMPORTANT RIDING POINTS
3MB-9-E7 12/27/00 2:52 PM Page 31

5-2
OPERATION AND IMPORTANT RIDING POINTS
1
2
3
45
6
7
8
9
IF TRANSMISSION IS IN NEUTRAL
AND SIDESTAND IS DOWN,KICK THE KICK STARTER.
ENGINE WILL START.RETRACT SIDESTAND AND PUT
TRANSMISSION IN GEAR.
MOTORCYCLE CAN BE RIDDEN.
MOTORCYCLE CAN BE RIDDEN.
IF TRANSMISSION IS IN GEAR
AND SIDESTAND IS UP,APPLY THE CLUTCH LEVER AND KICK
THE KICK STARTER.
ENGINE WILL START.
TURN THE MAIN SWITCH TO "ON" AND
THE ENGINE STOP SWITCH TO Ò#Ó.
3MB-9-E7 12/27/00 2:52 PM Page 32