2005 YAMAHA DT125R light

Control cables• Make sure that operation is smooth.
6-21• Lubricate if necessary.
• Check chain slack.
Drive chain• Adjust if necessary.
6-19/6-20
• Check chain condition.
• Lubricate if necessary.
• Check for damage.
Wheels and tires• Check tire condition and tread depth.
6-13
• Check air pressure.
• Correct if necessary.
Brake and shift pedals• Make sure that operation is smooth.
6-21
• Lubricate pedal pivoting points if necessary.
Brake and clutch levers• Make sure that operation is smooth.
6-21
• Lubricate lever pivoting points if necessary.
Sidestand• Make sure that operation is smooth.
6-21
• Lubricate pivot if necessary.
Chassis fasteners• Make sure that all nuts, bolts and screws are properly tightened.
–
• Tighten if necessary.
Instruments, lights,• Check operation.
–
signals and switches• Correct if necessary.
Engine stop switch• Check operation.3-3
Sidestand switch• Check operation of ignition circuit cut-off system.
3-11
• If system is defective, have Yamaha dealer check vehicle.
PRE-OPERATION CHECKS
4-3
4
1D0-F8199-E2.qxd 20/9/04 11:32 Página 26

EAU15950
EWA10270
s s
WARNING
Become 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 thoroughly
understand.
Never start the engine or ope-
rate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of cons-
ciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised comple-
tely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.
EAU16060
Starting a cold engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.
The transmission is in gear with
the clutch lever pulled and the
sidestand up.
EWA10290
s s
WARNING
Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-11.
Never 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 “f”.
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.
4. Turn the starter (choke) on and
completely close the throttle.
(See page 3-8.)
5. Start the engine by pushing the
start switch.
NOTE:
If the engine fails to start, release the
start switch, wait a few seconds, and
then try again. Each starting attempt
should be as short as possible to pre-
serve the battery. Do not crank the
engine more than 10 seconds on any
one attempt.
6. After starting the engine, move
the starter (choke) back halfway.
ECA11040
CAUTION
For maximum engine life, never
accelerate hard when the engine is
cold!
5
OPERATION AND IMPORTANT RIDING POINTS
5-1
1D0-F8199-E2.qxd 20/9/04 11:32 Página 29

7. When the engine is warm, turn
the starter (choke) off.
NOTE:
The engine is warm when it responds
normally to the throttle with the starter
(choke) turned off.
EAU16640
Starting a warm engine
Follow the same procedure as for
starting a cold engine with the excep-
tion that the starter (choke) is not
required when the engine is warm.
EAU16671
Shifting
Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing
hills, etc.
The gear positions are shown in the
illustration.
N. Neutral
1. Shift pedal
NOTE:
To shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of its
travel, and then slightly raise it.
ECA10260
CAUTION
Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long
distances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.
Always use the clutch while
changing gears to avoid dama-
ging the engine, transmission,
and drive train, which are not
designed to withstand the
shock of forced shifting.
EAU16830
Engine break-in
There is never a more important
period in the life of your engine than
the period between 0 and 1000 km
(600 mi). For this reason, you should
read the following material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1000 km (600 mi). The various parts in
the engine wear and polish themsel-
ves to the correct operating clearan-
ces. During this period, prolonged
full-throttle operation or any condition
that might result in engine overhea-
ting must be avoided.
EAU17150
0–150 km (0–90 mi)
Avoid prolonged operation above 1/3
throttle.
5
OPERATION AND IMPORTANT RIDING POINTS
5-2
1
1D0-F8199-E2.qxd 20/9/04 11:32 Página 30

ODOMETER READING (x 1000 Km) ANNUAL
CHECK
NoITEM CHECK OR MAINTENANCE JOB 1 6 12 18 24
22Transmission oil• Check oil level.√√ √ √√ √• Change.√√
23 *Cooling system• Check coolant level and vehicle for coolant leakage.√√√√ √• Change. Every 3 years
24 *Front and rear
• Check operation.√√ √ √√ √
brake switches
25Moving parts and cables• Lubricate.√√√√ √
Throttle grip • Check operation and free play.
26 * •Adjust the throttle cable free play if necessary.√√√√ √
housing and cable
• Lubricate the throttle grip housing and cable.
27 *Muffler and exhaust pipe• Check the screw clamp for looseness.√√ √ √√
28 *Lights, signals • Check operation.
and switches• Adjust headlight beam.√√ √ √√ √
PERIODIC MAINTENANCE AND MINOR REPAIR
6-4
6
EAU18670
NOTE:
The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinders and calipers, and change the bra-
ke fluid.
• Replace the brake hoses every four years and if cracked or damaged.
1D0-F8199-E2.qxd 20/9/04 11:32 Página 35

EAU19292
Panels D and E
1. Screw
To remove one of the panels
Remove the screw, and then pull the
panel off as shown.
T
o install the panel
Place the panel in the original posi-
tion, and then install the screw.
EAU19620
Checking the spark plug
1. Spark plug inspection
The spark plug is an important engine
component, which should be chec-
ked periodically, preferably by a
Yamaha dealer. Since heat and depo-
sits will cause any spark plug to
slowly erode, it 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.The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally). 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 vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon
or other deposits, it should be repla-
ced.
Specified spark plug:
BR8ES (NGK)
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
Spark plug gap:
0,7-0,8 mm (0,0276-0,0315 in)
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
11
1D0-F8199-E2.qxd 20/9/04 11:32 Página 37

Tightening torque:
Spark plug:
20 Nm (2 m•kgf)
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. Howe-
ver, the spark plug should be tighte-
ned to the specified torque as soon
as possible.
EAU19950
Transmission oil
1. Oil level window
2. Maximum level mark
3. Minimum level mark
The transmission oil level should be
checked before each ride. In addition,
the transmission oil must be changed
at the intervals specified in the perio-
dic maintenance and lubrication
chart.
To check the transmission oil level
1. Place the vehicle on a level surfa-
ce and hold it in an upright posi-
tion.
NOTE:
Make sure that the vehicle is positio-
ned straight up when checking the oil
level. A slight tilt to the side can result
in a false reading.
1. Plug to fill with oil
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 right side of the
crankcase.
NOTE:
The transmission oil should be at or
above the minimum level mark.
4. If the oil is below the minimum
level mark, remove the oil filler
cap, add sufficient oil of the
recommended type to raise it to
the correct level, and then install
and tighten the cap.
To change the transmission oil
1. Drain bolt
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
2
3
11
1
1D0-F8199-E2.qxd 20/9/04 11:32 Página 38

1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the trans-
mission to collect the used oil.
3. Remove the oil filler cap and
drain bolt to drain the oil from the
transmission.
4. Install the transmission oil drain
bolt, and then tighten it to the
specified torque.
Tightening torque:
Transmission oil drain bolt:
15 Nm (1,5 m•kgf)
5. Add the specified amount of the
recommended transmission oil,
and then install and tighten the oil
filler cap.
Recommended transmission oil:
See page 8-1.
Oil change quantity:
0,8 L (0,85 US qt)
ECA10450
CAUTION
In order to prevent clutch slip-
page (since the transmission
oil also lubricates the clutch),
do not mix any chemical additi-
ves with the oil.
Make 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, imme-
diately turn off the engine and
check for the cause.
EAU20070
Coolant
The coolant level should be checked
before each ride. In addition, the coo-
lant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU20170
To check the coolant level
1. Place the vehicle on a level surfa-
ce and hold it in an upright posi-
tion.
NOTE:
The coolant level must be chec-
ked on a cold engine since the
level varies with engine tempera-
ture.
Make sure that the vehicle is
positioned straight up when
checking the coolant level. A
slight tilt to the side can result in
a false reading.
2. Remove panel D. (See page 6-6.)
3. Check the coolant level in the
coolant reservoir.
FULL
LOW
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
1D0-F8199-E2.qxd 20/9/04 11:32 Página 39

EAU22192
Adjusting the brake pedal
position and free play
1. Footrest
(a) Brake pedal position
EWA10670
s s
WARNING
It is advisable to have a Yamaha
dealer make these adjustments.
Brake pedal position
The top of the brake pedal should be
positioned approximately 12-15 mm
(0,47-0,49 in) below the top of the
footrest. Periodically check the brake
pedal position and, if necessary,
adjust it as follows.
1. Loosen the locknut at the brake
pedal.2. To raise the brake pedal, turn the
adjusting bolt in direction (a). To
lower the brake pedal, turn the
adjusting bolt in direction (b).
3. Tighten the locknut.
EWA11230
s s
WARNING
After adjusting the brake pedal
position, the brake pedal free play
must be adjusted.
Brake pedal free play
The brake pedal free play should
measure 10-15 mm (0,34-0,59 in) as
shown. Periodically check the brake
pedal free play and, if necessary,
adjust it as follows.
To increase the brake pedal free play,
turn the adjusting nut at the brake rod
in direction (a). To decrease the brake
pedal free play, turn the adjusting nut
in direction (b).
EWA10680
s s
WARNING
After adjusting the drive chain
slack or removing and installing
the rear wheel, always check
the brake pedal free play.
If proper adjustment cannot be
obtained as described, have a
Yamaha dealer make this
adjustment.
After adjusting the brake pedal
free play, check the operation
of the brake light.
EAU22270
Adjusting the rear brake light
switch
1. Brake light swicht
2. Adjusting nut
The rear brake light switch, which is
activated by the brake pedal, is pro-
perly adjusted when the brake light
comes on just before braking takes
effect. If necessary, adjust the brake
light switch as follows.
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
1
1
2
1D0-F8199-E2.qxd 20/9/04 11:32 Página 48