YAMAHA DT125R 2000 Repair Manual

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98Use only the designated quality
brake fluid. Otherwise, the rub-
ber seals may deteriorate, caus-
ing leakage and poor brake per-
formance.
NOTE:
If DOT 4 is not available, DOT 3 can
be used.
EAU00732
Inspecting the brake fluid
levelInsufficient brake fluid may let air
enter the brake system, possibly
causing the brakes to become inef-
fective.
Before riding, check that the brake
fluid is above the minimum level and
fill when necessary.
Observe these precautions:
8When checking the fluid level,
make sure the top of the master
cylinder is level by turning the
handlebars.
1
1.Minimum level mark FRONT
1
1.Minimum level markREARRecommended brake fluid:
DOT 4
8Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor brake performance.
8Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the fluid
and may result in vapor lock.
8Brake fluid may deteriorate paint-
ed surfaces or plastic parts.
Always clean up spilled fluid
immediately.
8Have a Yamaha dealer check
the cause if the brake fluid level
goes down.
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EAU00742
Brake fluid replacementThe brake fluid should be replaced
only by trained Yamaha service per-
sonnel. Have the Yamaha dealer
replace the following components
during periodic maintenance or when
they are damaged or leaking:
8oil seals (every two years)
8brake hoses (every four years)
EAU00744*
Drive chain slack checkNOTE:
Spin the wheel several times and find
the tightest position of the chain.
Check and/or adjust the chain slack
while itÕs in this tightest position.
a
a.Chain slack
To check the chain slack the motor-
cycle must be held straight up with
both wheels on the ground and with-
out rider. Check the slack at the posi-
tion shown in the illustration. Normal
slack is approximately 25 ~ 40 mm. If
the slack exceeds 40 mm, adjust it.
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EC000096
cCToo little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits.3.Tighten the wheel axle nut to the
specified torque.
EAU01533*
Drive chain slack adjustment1.Loosen the wheel axle nut.
2.To tighten the chain, turn the
chain adjusting plates in direction
a. To loosen the chain, turn the
chain adjusting plates in direction
band push the wheel forward.
Turn each chain adjusting plate
to exactly the same position to
maintain correct axle alignment.
a b
2
1
1.Wheel axle nut
2.Chain adjusting plate
Tightening torque:
Wheel axle nut:
90 Nm (9.0 m
0kg)
EAU03006
Drive chain lubricationThe chain consists of many parts
which work with each other. If the
chain is not maintained properly, it
will wear out quickly. Therefore, the
chain must be serviced regularly.
This service is especially necessary
when riding in dusty areas. This
motorcycle is equipped with a sealed
type chain. Steam cleaning, high-
pressure washers, and solvents can
damage the drive chain, so do not
use these for cleaning it. Use only
kerosene to clean the drive chain.
Wipe it dry, and thoroughly lubricate it
with SAE 30 ~ 50W motor oil. Do not
use any other lubricants on the drive
chain. They may contain solvents
that could damage the sealed chain.
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EC000097
cCBe sure to oil the chain after wash-
ing the motorcycle or riding in the
rain.
EAU02962
Cable inspection and
lubrication
EW000112
wDamage to the outer housing of
cables may lead to internal rusting
and interfere with the cable move-
ment. Replace damaged cables as
soon as possible to prevent unsafe
conditions.Lubricate the cables and cable ends.
If a cable does not operate smoothly,
ask a Yamaha dealer to replace it.
EAU00773
Throttle cable and grip
lubricationThe throttle twist grip assembly
should be greased at the time that
the cable is lubricated, since the grip
must be removed to get at the end of
the throttle cable. After removing the
screws, hold the end of the cable up
in the air and put in several drops of
lubricant. With the throttle grip disas-
sembled, coat the metal surface of
the grip assembly with a suitable all-
purpose grease.
Recommended lubricant:
Engine oil
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EAU00774
Autolube pump adjustmentThe autolube pump is a vital part of
the engine and requires very sophisti-
cated adjustment.
Adjusting should be left to a Yamaha
dealer who has the professional
knowledge and experience to do so.
EAU02984
Brake and shift pedal
lubricationLubricate the pivoting parts.
EAU02985
Brake and clutch lever
lubricationLubricate the pivoting parts.
Recommended lubricant:
Engine oil
Recommended lubricant:
Engine oil
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EAU02986
Sidestand lubricationLubricate the sidestand pivoting point
and metal-to-metal contact surfaces.
Check that the sidestand moves up
and down smoothly.
EW000113
wIf the sidestand does not move
smoothly, consult a Yamaha deal-
er.
Recommended lubricant:
Engine oil
EAU02939
Front fork inspectionVisual check
EW000115
wSecurely support the motorcycle
so there is no danger of it falling
over.Check for scratches or damage on
the inner tube and excessive oil leak-
age from the front fork.Operation check
1.Place the motorcycle on a level
place.
2.Hold the motorcycle in an upright
position and apply the front
brake.
3.Push down hard on the handle-
bars several times and check if
the fork rebounds smoothly.
EC000098
cCIf any damage or unsmooth move-
ment is found with the front fork,
consult a Yamaha dealer.
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EAU00794
Steering inspectionPeriodically inspect the condition of
the steering. Worn out or loose steer-
ing bearings may be dangerous.
Place a stand under the engine to
raise the front wheel off the ground.
Hold the lower end of the front forks
and try to move them forward and
backward. If any free play can be felt,
ask a Yamaha dealer to inspect and
adjust the steering. Inspection is eas-
ier if the front wheel is removed.
EW000115
wSecurely support the motorcycle
so there is no danger of it falling
over.
EAU01144
Wheel bearingsIf there is play in the front or rear
wheel hub or if the wheel does not
turn smoothly, have a Yamaha dealer
inspect the wheel bearings.
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EAU01071
BatteryCheck the level of the battery elec-
trolyte and make sure that the termi-
nals are tight.
Fill with distilled water if the elec-
trolyte level is low.1.Battery
2.Battery breather hose
EC000099
cCWhen inspecting the battery, be
sure the breather hose is routed
correctly. If the breather hose is
positioned in such a way as to
cause battery electrolyte or gas to
exit onto the frame, structural and
cosmetic damage to the motorcy-
cle can occur.
12
EW000116
wBattery electrolyte is poisonous
and dangerous, causing severe
burns, etc. It contains sulfuric
acid. Avoid contact with skin, eyes
or clothing.
ANTIDOTE:
8 8
EXTERNAL: Flush with water.
8 8
INTERNAL: Drink large quanti-
ties of water or milk. Follow
with milk of magnesia, beaten
egg, or vegetable oil. Call a
physician immediately.
8 8
EYES: Flush with water for 15
minutes and get prompt med-
ical attention.
Batteries produce explosive
gases. Keep sparks, flame, ciga-
rettes etc., away. Ventilate when
charging or using in an enclosed
space. Always shield your eyes
when working near batteries.
KEEP OUT OF REACH OF CHIL-
DREN.
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9Replenishing the battery fluid
A poorly maintained battery will cor-
rode and discharge quickly. The bat-
tery fluid should be checked at least
once a month. The level should be
between the minimum level and max-
imum level marks. Use only distilled
water if refilling is necessary.
EC000100
cCNormal tap water contains miner-
als which are harmful to a battery;
therefore, refill only with distilled
water.
EW000117
wTake care not to spill battery fluid
on the chain.
Battery fluid may weaken the chain
causing shorter chain life and pos-
sibly result in an accident.
1.Maximum level mark
2.Minimum level mark
1
2
Battery storage
8When the motorcycle will not be
used for a month or longer,
remove the battery, fully charge
it and store it in a cool, dry place.
Completely recharge the battery
before reinstallation.
8If the battery will be stored for
longer than two months, check
the specific gravity of the fluid at
least once a month and fully
recharge the battery when it is
too low.
8Always make sure the connec-
tions are correct when putting
the battery back in the motorcy-
cle. Make sure the breather hose
is properly connected and is not
damaged or obstructed.
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EAU00804
Fuse replacementIf the fuse is blown, turn off the main
switch and the switch of the circuit in
question. Install a new fuse of speci-
fied amperage. Turn on the switches
and see if the electrical device oper-
ates. If the fuse immediately blows
again, consult a Yamaha dealer.1.Fuse
EC000103
cCDo not use fuses of higher amper-
age rating than those recommend-
ed. Substitution of a fuse of
improper rating can cause exten-
sive electrical system damage and
possibly a fire.
Specified fuse:
10 A
1
1
1.Bolt (´2)
EAU01158
Headlight bulb replacementIf the headlight bulb burns out,
replace the bulb as follows:
1.Remove cowling A. (See page
6-6 ~ 6-7 for removal and instal-
lation procedures.)
2.Remove the headlight unit by
removing the bolts.
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