2005 YAMAHA DT125R Owners 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.
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FRONTREAR
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Recommended brake fluid:
DOT 4
Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking performan-
ce.
Be careful that water does not
enter the brake fluid reservoir
when refilling. Water will signifi-
cantly lower the boiling point of
the fluid and may result in vapor
lock.
Brake fluid may deteriorate pain-
ted surfaces or plastic parts.
Always clean up spilled fluid
immediately.
As the brake pads wear, it is nor-
mal for the brake fluid level to
gradually go down. However, if
the brake fluid level goes down
suddenly, have a Yamaha dealer
check the cause.
EAU22730
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addi-
tion, have the oil seals of the master
cylinders and calipers as well as the
brake hoses replaced at the intervals
listed below or whenever they are
damaged or leaking.
Oil seals: Replace every two
years.
Brake hoses: Replace every four
years.
EAU22770
To check the drive chain slack
(a) Chain tension
1. Place the motorcycle on a level
surface and hold it in an upright
position.
NOTE:
When checking and adjusting the dri-
ve chain slack, the motorcycle should
be positioned straight up and there
should be no weight on it.
2. Shift the transmission into the
neutral position.
3. Move the rear wheel by pushing
the motorcycle to locate the tigh-
test portion of the drive chain,
and then measure the drive chain
slack as shown.
Drive chain slack:
45-55 mm (1,76-2,15 in)
4. If the drive chain slack is inco-
rrect, adjust it as follows.
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EAU22960
To adjust the drive chain slack
1. Axle nut
2. Chain tensioner
1. Loosen the axle nut.
2. To tighten the drive chain, turn
the adjusting plate on each side
of the swingarm in direction (a).
To loosen the drive chain, turn
the adjusting plate on each side
of the swingarm in direction (b),
and then push the rear wheel for-
ward.
NOTE:
Make sure that both adjusting plates
are in the same position for proper
wheel alignment.
ECA10570
CAUTION
Improper drive chain slack will
overload the engine as well as
other vital parts of the motorcycle
and can lead to chain slippage or
breakage. To prevent this from
occurring, keep the drive chain
slack within the specified limits.
3. Tighten the axle nut to the speci-
fied torque.
Tightening torque:
Axle nut:
90 Nm (9,0 m•kgf)
EAU23021
Lubricating the drive chain
The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly
wear out, especially when riding in
dusty or wet areas. Service the drive
chain as follows.
ECA10581
CAUTION
The drive chain must be lubricated
after washing the motorcycle and
riding in the rain.
1. Clean the drive chain with kero-
sene and a small soft brush.
ECA11120
CAUTION
To prevent damaging the O-rings,
do not clean the drive chain with
steam cleaners, high-pressure
washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant.
ECA11110
CAUTION
Do not use engine oil or any other
lubricants for the drive chain, as
they may contain substances that
could damage the O-rings.
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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.
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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.
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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.
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2. If the battery will be stored for
more than two months, check it
at least once a month and fully
charge it if necessary.
3. Fully charge the battery before
installation.
4. After installation, make sure that
the battery leads are properly
connected to the battery termi-
nals.
ECA10630
CAUTION
Always keep the battery char-
ged. Storing a discharged bat-
tery can cause permanent bat-
tery damage.
To charge a sealed-type (MF)
battery, a special (constant-
voltage) battery charger is
required. Using a conventional
battery charger will damage
the battery. If you do not have
access to a sealed-type (MF)
battery charger, have a Yamaha
dealer charge your battery.
EAUS1180
Replacing the fuse
1. Fuse
2. Reserve fuse
The fuse holder is located beside the
battery case.
If the fuse is blown, replace it as
follows.
1. Turn the key to “OFF” and turn off
all electrical circuits.
2. Remove the blown fuse, and then
install a new fuse of the specified
amperage.
Specified fuse:
15 A
ECA10640
CAUTION
Do not use a fuse of a higher ampe-
rage rating than recommended to
avoid causing extensive damage to
the electrical system and possibly a
fire.
3. Turn the key to “ON” and turn on
the electrical circuits to check if
the devices operate.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
EAU23910
Replacing a headlight bulb
1. Couplers
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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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