warning YAMAHA DT125R 2006 Owner's Manual

Turn the adjusting nut while holding
the rear brake light switch in place. To
make the brake light come on earlier,
turn the adjusting nut in direction (a).
To make the brake light come on later,
turn the adjusting nut in direction (b).
EAU22340
Checking the front and rear
brake pads
1. Wear limit indicator
The front and rear brake pads must
be checked for wear at the intervals
specified in the periodic maintenance
and lubrication chart. To check the
brake pad wear, measure the lining
thickness. If the lining thickness is
less than 0,8 mm (0,03 in), have a
Yamaha dealer replace the brake
pads as a set.
EWA10250
s s
WARNING
If a malfunction is noted, have a
Yamaha dealer check the system
before riding.
1. Wear indicator
EAU22580
Checking the brake fluid level
1. Minimum level mark
Insufficient brake fluid may allow air
to enter the brake system, possibly
causing it to become ineffective.Before riding, check that the brake
fluid is above the minimum level mark
and replenish if necessary. A low bra-
ke fluid level may indicate worn brake
pads and/or brake system leakage. If
the brake fluid level is low, be sure to
check the brake pads for wear and
the brake system for leakage.
Observe these precautions:
When checking the fluid level,
make sure that the top of the
brake fluid reservoir is level.
1. Minimum level mark

Use only the recommended qua-
lity brake fluid, otherwise the rub-
ber seals may deteriorate, cau-
sing leakage and poor braking
performance.
6
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FRONTREAR
FRONTREAR
11
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EAU23100
Checking and lubricating the
cables
The operation of all control cables
and the condition of the cables
should be checked before each ride,
and the cables and cable ends should
be lubricated if necessary. If a cable is
damaged or does not move smoothly,
have a Yamaha dealer check or repla-
ce it.
Recommended lubricant:
Engine oil
EWA10720
s s
WARNING
Damage to the outer sheath may
interfere with proper cable opera-
tion and will cause the inner cable
to rust. Replace a damaged cable
as soon as possible to prevent
unsafe conditions.
EAU23110
Checking and lubricating the
throttle grip and cable
The operation of the throttle grip
should be checked before each ride.
In addition, the cable should be lubri-
cated or replaced at the intervals spe-
cified in the periodic maintenance
chart.
EAU23120
Adjusting the Autolube pump
The Autolube pump is a vital and sop-
histicated component of the engine,
which must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
EAU23131
Checking and lubricating the
brake and shift pedals
The operation of the brake and shift
pedals should be checked before
each ride, and the pedal pivots
should be lubricated if necessary.
Recommended lubricant:
Lithium-soap-based grease (all-pur-
pose grease)
EAU23140
Checking and lubricating the
brake and clutch levers
The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be
lubricated if necessary.
Recommended lubricant:
Lithium-soap-based grease (all-pur-
pose grease)
EAU23200
Checking and lubricating the
sidestand
The operation of the sidestand should
be checked before each ride, and the
sidestand pivot and metal-to-metal
contact surfaces should be lubricated
if necessary.
EWA10730
s s
WARNING
If the sidestand does not move up
and down smoothly, have a Yama-
ha dealer check or repair it.
6
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Recommended lubricant:
Lithium-soap-based grease (all-pur-
pose grease)
EAU23271
Checking the front fork
The condition and operation of the
front fork must be checked as follows
at the intervals specified in the perio-
dic maintenance and lubrication
chart.
To check the condition
EWA10750
s s
WARNING
Securely support the motorcycle so
that there is no danger of it falling
over.
Check the inner tubes for scratches,
damage and excessive oil leakage.To check the operation
1. Place the motorcycle on a level
surface and hold it in an upright
position.
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and
rebounds smoothly.ECA10590
CAUTION
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or
repair it.
EAU23280
Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the opera-
tion of the steering must be checked
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
1. Place a stand under the engine to
raise the front wheel off the
ground.
EWA10750
s s
WARNING
Securely support the motorcycle so
that there is no danger of it falling
over.
6
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2. Hold the lower ends of the front
fork legs and try to move them
forward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the stee-
ring.
EAU23290
Checking the wheel bearings
The front and rear wheel bearings
must be checked at the intervals spe-
cified in the periodic maintenance and
lubrication chart. If there is play in the
wheel hub or if the wheel does not
turn smoothly, have a Yamaha dealer
check the wheel bearings.
EAU23380
Battery
1. Battery
2. Battery ventilation pipe
The battery is located behind panel D.
(See page 6-6.)
This model is equipped with a sealed-
type (MF) battery, which does not
require any maintenance. There is no
need to check the electrolyte or to
add distilled water.
ECA10620
CAUTION
Never attempt to remove the bat-
tery cell seals, as this would per-
manently damage the battery.
EWA10760
s s
WARNING
Electrolyte is poisonous and
dangerous since it contains
sulfuric acid, which causes
severe burns. Avoid any con-
tact with skin, eyes or clothing
and always shield your eyes
when working near batteries.
In case of contact, administer
the following FIRST AID.
• EXTERNAL: Flush with plenty
of water.
• INTERNAL: Drink large quan-
tities of water or milk and
immediately call a physician.• EYES: Flush with water for 15
minutes and seek prompt
medical attention.
• Batteries produce explosive
hydrogen gas. Therefore,
keep sparks, flames, cigaret-
tes, etc., away from the bat-
tery and provide sufficient
ventilation when charging it
in an enclosed space.
KEEP THIS AND ALL BATTE-
RIES OUT OF THE REACH OF
CHILDREN.
To charge the battery
Have a Yamaha dealer charge the
battery as soon as possible if it seems
to have discharged. Keep in mind that
the battery tends to discharge more
quickly if the vehicle is equipped with
optional electrical accessories.
To store the battery
1. If the vehicle will not be used for
more than one month, remove
the battery, fully charge it, and
then place it in a cool, dry place.
6
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This model is equipped with quartz
bulb headlights. If a headlight bulb
burns out, replace it as follows.
1. Remove cowling A. (See page
6-5.)
2. Disconnect the headlight coupler,
and then remove the headlight
bulb cover.
3. Remove the headlight bulb hol-
der according to the following
illustration, and then remove the
defective bulb.
NOTE:
The removal procedure depends on
the type of bulb holder installed on
your vehicle.
EWA10790
s s
WARNING
Headlight bulbs get very hot. The-
refore, keep flammable products
away from a lit headlight bulb, and
do not touch the bulb until it has
cooled down.
4. Place a new bulb into position,
and then secure it with the bulb
holder.
ECA10660
CAUTION
Do not touch the glass part of the
headlight bulb to keep it free from
oil, otherwise the transparency of
the glass, the luminosity of the
bulb, and the bulb life will be adver-
sely affected. Thoroughly clean off
any dirt and fingerprints on the
headlight bulb using a cloth mois-
tened with alcohol or thinner.
5. Install the bulb cover, and then
connect the coupler.
6. Install the cowling.
7. Have a Yamaha dealer adjust the
headlight beam if necessary.
EAU24131
Replacing the tail/brake light
bulb
1. Screw (x2)
2. Lens
1. Remove the tail/brake light lens
by removing the screws.
2. Remove the defective bulb by
pushing it in and turning it coun-
terclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screws.6
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EWA10820
s s
WARNING
It is advisable to have a Yama-
ha dealer service the wheel.
Securely support the motorcy-
cle so that there is no danger of
it falling over.
1. Disconnect the speedometer
cable from the front wheel.
2. Loosen the wheel axle holder
nuts, then the wheel axle.
3. Lift the front wheel off the ground
according to the procedure on
page 6-26.
4. Pull the wheel axle out, and then
remove the wheel.
ECA11070
CAUTION
Do not apply the brake after the
wheel has been removed together
with the brake disc, otherwise the
brake pads will be forced shut.
EAU24950
To install the front wheel
1. Install the speedometer gear unit
into the wheel hub so that the
projections mesh with the slots.
2. Lift the wheel up between the
fork legs.
NOTE:
Make sure that there is enough space
between the brake pads before inser-
ting the brake disc and that the slot in
the speedometer gear unit fits over
the retainer on the fork leg.
3. Insert the wheel axle.
4. Lower the front wheel so that it is
on the ground.
5. Tighten the wheel axle to the
specified torque.
Tightening torque:
Wheel axle:
55 Nm (5,5 m•kgf)
6. Tighten the axle holder nuts to
the specified tightening torque. Tigh-
ten the upper nuts first and then lower
ones. When tightened in this sequen-
ce, there should be a gap formed at
the bottom of the axle holder.
Tightening torque:
Axle holder nut:
10 Nm (1,0 m•kgf)
6
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1. Gap
7. After tightening the axle holder
nuts, push down hard on the
handlebars several times while
applying the front brake to check
if the front fork compresses and
rebounds smoothly.
8. Connect the speedometer cable.
EAU25080
Rear wheel
EAU25230
To remove the rear wheel
1. Axle retainer bolt
EWA10820
s s
WARNING
It is advisable to have a Yama-
ha dealer service the wheel.
Securely support the motorcy-
cle so that there is no danger of
it falling over.
1. Loosen the axle nut.
2. Lift the rear wheel off the ground
according to the procedure on
page 6-26.
1. Axle nut
2. Chain tensioner
3. Remove the swingarm end bolts.
4. Turn the drive chain adjusting
plate on each side of the swin-
garm fully in direction (a).
5. Push the wheel forward, and then
remove the drive chain from the
rear sprocket.
NOTE:
The drive chain does not need to be
disassembled in order to remove and
install the rear wheel.
6. Pull the wheel axle out from the
left-hand side, and then remove
the wheel by pulling it back.
6
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ECA11070
CAUTION
Do not apply the brake after the
wheel has been removed together
with the brake disc, otherwise the
brake pads will be forced shut.
EAU25530
To install the rear wheel
1. Install the drive chain onto the
rear sprocket, and then insert the
wheel axle from the left-hand
side.
NOTE:
Make sure that there is enough space
between the brake pads before inser-
ting the brake disc between the brake
pads.
2. Install the drive chain adjusting
plates.
NOTE:
Make sure that the drive chain adjus-
ting plates are installed with the pun-
ched side facing to the outside.
3. Install the swingarm end bolts.4. Adjust the drive chain slack. (See
page 6-19.)
5. Tighten the axle nut and the
swingarm end bolts to the speci-
fied torques, and then install the
cotter pin.
EWA10700
s s
WARNING
Always use a new cotter pin for the
axle nut.
Tightening torque:
Axle nut:
90 Nm (9,0 m•kgf)
Swingarm end bolt:
3 Nm (0,3 m•kgf)
EAU25850
Troubleshooting
Although Yamaha motorcycles recei-
ve a thorough inspection before ship-
ment from the factory, trouble may
occur during operation. Any problem
in the fuel, compression, or ignition
systems, for example, can cause poor
starting and loss of power.The following troubleshooting chart
represents a quick and easy procedu-
re for checking these vital systems
yourself. However, should your
motorcycle require any repair, take it
to a Yamaha dealer, whose skilled
technicians have the necessary tools,
experience, and know-how to service
the motorcycle properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
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EAU25921
Troubleshooting charts
Starting problems or poor engine performanceEWA10840
s s
WARNING
Keep away open flames and do not smoke while checking or working on the fuel system.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-30
6
Check the fuel level in
the fuel tank.
1. FuelThere is enough fuel.
There is no fuel.Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.
2. CompressionThere is compression.
There is no compression.Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.
3. IgnitionWipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.
4. BatteryThe engine turns over
quickly.
The engine turns over
slowly.The battery is good.
Check the battery lead connections,
and charge the battery if necessary.
Dry
WetOpen the throttle halfway and operate
the electric starter.
1D0-F8199-E2.qxd 20/9/04 11:32 Página 61

NOTE:
If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended
coolant as soon as possible.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-31
6Wait until the
engine has cooled.Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.
The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.
Add coolant. (See NOTE.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
Engine overheatingEWA10400
s s
WARNING
Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the his-
sing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
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