engine YAMAHA DT125R 2000 Owner's Guide

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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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122
1.Disc cover
2.Screw (´2)
EAU00898
Front wheel removal
EW000122
w8
8
It is advisable to have a
Yamaha dealer service the
wheel.
8 8
Securely support the motorcy-
cle so there is no danger of it
falling over.1.Remove the disc cover.
2.Remove the speedometer cable
from the front wheel side.
EAU01579
Supporting the motorcycleSince the Yamaha DT125R has no
centerstand, follow these precautions
when removing the front and rear
wheel or performing other mainte-
nance requiring the motorcycle to
stand upright. Check that the motor-
cycle is in a stable and level position
before starting any maintenance. A
strong wooden box can be placed
under the engine for added stability.
Front wheel service
To stabilize the rear of the motorcy-
cle, either use a motorcycle stand or
place a motorcycle jack under the
frame in front of the rear wheel to
prevent it from moving from side to
side. Then use a motorcycle stand to
elevate the front wheel off of the
ground.Rear wheel service
Use a motorcycle stand or motorcycle
jack to elevate the motorcycle so the
rear wheel is off the ground.
Alternatively, two jacks can be placed
under the frame or swingarm.
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2 1
3.Elevate the front wheel by plac-
ing a suitable stand under the
engine.
4.Loosen the wheel axle holder
nuts.
5.Remove the wheel axle and the
front wheel. Make sure the
motorcycle is properly supported.NOTE:
Do not depress the brake lever when
the disc and caliper are separated.
EAU03104
Front wheel installation1.Install the speedometer gear unit
housing into the wheel hub.
Make sure the speedometer gear
unit housing is installed with the
projections meshed into the
slots.
2.Lift up the wheel between the
front fork legs and guide the
brake disc between the brake
pads. Make sure there is enough
gap between the brake pads
before inserting the brake disc.
1.Speedometer cable
2.Axle holder nut (´4)
3.Wheel axle
3.Make sure the slot in the
speedometer gear unit fits over
the stopper on the front fork
outer tube.
4.Install the wheel axle and let the
motorcycle down.
5.Tighten the wheel axle the speci-
fied torque.
Tightening torque:
Wheel axle:
58 Nm (5.8 m
0kg)
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1
1
1.Swingarm end bolt (´2)
EAU03105
Rear wheel removal
EW000122
w8
8
It is advisable to have a
Yamaha dealer service the
wheel.
8 8
Securely support the motorcy-
cle so there is no danger of it
falling over.1.Loosen the rear axle nut.
2.Elevate the rear wheel by placing
a suitable stand under the
engine.
3.Remove the swingarm end bolts.4.Remove the axle nut.
5.Push the wheel forward and
remove the drive chain.
6.Pull out the rear axle and remove
the wheel assembly by pulling
backward.
NOTE:
8Do not depress the brake pedal
when the disc and caliper are
separated.
8You do not have to disassemble
the chain in order to remove or
install the rear wheel.
2
1
1.Axle nut
2.Chain adjusting plate
6.Tighten the axle holder nuts to
the specified tightening torque.
Tighten the upper nuts first and
then lower ones. When tightened
in this sequence, there should be
a gap formed at the bottom of
the axle holder.
7.After tightening the holder nuts,
push down on the handlebars
several times and check if the
fork rebounds smoothly. Tightening torque:
Axle holder nut:
10 Nm (1.0 m
0kg)1
1.Gap
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EAU03108
Troubleshooting charts
EW000125
wNever check the fuel system while smoking or in the vicinity of an open flame.Check if there is fuel1. Fuel
Enough fuel.
No fuel.
Go to compression check.
Supply fuel.
Engine doesn’t start, go to compression check.
Use kick starter.2. Compression
There is compression.
No compression.
Go to ignition check.
Ask a Yamaha dealer to
Remove spark plug3. Ignition
Wet.
Dry.
Wipe clean with dry cloth and correct
Ask a Yamaha dealer to inspect.
Engine doesn’t start, ask a YamahaOpen throttle half-way and start
in the fuel tank.
and check electrodes.spark gap or replace spark plug.the engine.
dealer to inspect. inspect.
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4. Engine overheating
EW000070
wDo 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. Open the radiator cap as follows. Wait until the
engine has cooled. Remove the radiator cap stopper by removing the screw. Place a thick rag like a towel over
the radiator cap and slowly rotate the cap counterclockwise to the detent. This procedure allows any residual
pressure to escape. When the hissing sound has stopped, press down on the cap while turning counterclock-
wise and remove it.Wait until the
Check the coolant level in the
Level is OK.Level is low, check the
NoLeakage.
Ask a Yamaha dealer to inspectAdd coolant. (See NOTE.)
Restart the engine. If the engine overheats again, ask a
engine has cooled.reservoir tank and/or radiator.cooling system for leakage.
Yamaha dealer to inspect and repair the cooling system. leakage.
and repair the cooling system.
NOTE:
If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is changed to the rec-
ommended coolant as soon as possible.
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