2000 YAMAHA DT125R engine

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95.Fill the engine with sufficient oil
to reach the specified level.
Install the oil filler cap and tight-
en it.
EC000079
cCDo not put in any chemical addi-
tives. Transmission oil also lubri-
cates the clutch and additives
could cause clutch slippage.6.Start the engine and warm up for
a few minutes. While warming
up, check for oil leakage. If oil
leakage is found, stop the engine
immediately and check for
cause. Recommended oil:
See page 8-1.
Oil quantity:
Total amount: 0.8 L
Periodic oil change: 0.75 L
1
Transmission oil replacement
1.Warm up the engine for several
minutes.
2.Stop the engine. Place an oil pan
under the engine to catch the oil
and remove the oil filler cap.
3.Remove the drain bolt and drain
the oil.
4.Install the drain bolt and tighten it
to the specified torque.1.Drain bolt
Tightening torque:
Drain bolt:
15 Nm (1.5 m
0kg)
1
2.With the engine stopped, check
the oil level through the level
window located at the right side
crankcase cover.NOTE:
Wait a few minutes until the oil level
settles before checking.3.The oil level should be between
the maximum and minimum level
on the level window. If the level
is low, add sufficient oil to raise it
to the specified level.1.Oil filler cap
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EAU01808
Cooling system1.Remove panel D. (See page 6-9
for panel removal and installation
procedures.)
2.Check the coolant level in the
reservoir tank when the engine is
cold as the coolant level will vary
with engine temperature. The
coolant level should be between
the maximum and minimum
marks.
3.If the level is low, add coolant or
distilled water to raise it to the
specified level.4.Install the panel.
EC000080
cCHard water or salt water is harmful
to the engine. You may use dis-
tilled water if you canÕt get soft
water.NOTE:
If water is added, have a Yamaha
dealer check the antifreeze content of
the coolant as soon as possible.If your motorcycle overheats, see
page 6-41 for details.
2
1
1.Maximum level mark
2.Minimum level mark
EAU03101
Changing the coolant1.Put the motorcycle on a level
place.
2.Remove cowling C and panel D.
(See page 6-8 ~ 6-9 for cowling
and panel removal and installa-
tion procedures.)
3.Remove the radiator cap stopper
bolt and the radiator cap.
12
1.Stopper bolt
2.Radiator cap
Reservoir tank capacity:
0.35 L
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98.Install the reservoir tank hose.
9.Pour the recommended coolant
into the radiator until it is full.
Recommended antifreeze:
High quality ethylene glycol
antifreeze containing
corrosion inhibitors for
aluminum engines.
Antifreeze and water mixing ratio:
1:1
Total amount:
1.05 L
Reservoir tank capacity:
0.35 L
4.Place a container under the
engine and remove the coolant
drain bolt.5.Disconnect the reservoir tank
hose on the reservoir tank side
and drain the coolant from the
reservoir tank.
6.After draining the coolant, thor-
oughly flush the cooling system
with clean tap water.
7.Replace the coolant drain bolt
washer if it is damaged and tight-
en the coolant drain bolt to the
specified torque.
1
13
2
1.Drain bolt1.Reservoir tank hose
2.Maximum level mark
3.Minimum level mark
Tightening torque:
Coolant drain bolt:
10 Nm (1.0 m
0kg)
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EC000080
cCHard water or salt water is harmful
to the engine. You may use dis-
tilled water if you canÕt get soft
water.10.Install the radiator cap.
11.Run the engine several minutes.
Stop the engine and recheck the
coolant level in the radiator. If it
is low, add more coolant until it
reaches the top of the radiator.
12.Install the radiator cap stopper
bolt.
13.Fill the reservoir tank with
coolant up to maximum level.
14.Install the reservoir tank cap and
check for coolant leakage.NOTE:
If any leakage is found, ask a
Yamaha dealer to inspect the cooling
system.15.Install the cowling and the panel.
1
EAU03107
Air filterThe air filter should be cleaned at the
specified intervals. It should be
cleaned more frequently when riding
in unusually wet or dusty areas.
1.Remove panel D. (See page 6-9
for panel removal and installation
procedures.)
2.Remove the air filter case by
removing the screws.1.Screw (´3)
3.Remove the air filter from the
case.
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96.Insert the air filter guide into the
air filter and install it in the case.
7.Install the air filter case cover
and panel by installing the
screws.
EC000082
cC8
8
Make sure the air filter is prop-
erly seated in the air filter
case.
8 8
The engine should never be
run without the air filter
installed. Excessive piston
and/or cylinder wear may
result.
EAU00629
Carburetor adjustmentThe carburetor is a vital part of the
engine and requires very sophisticat-
ed adjustment. Most adjustments
should be left to a Yamaha dealer
who has the professional knowledge
and experience to do so. However,
the following may be serviced by the
owner as part of routine mainte-
nance.
EC000094
cCThe carburetor was set at the
Yamaha factory after many tests. If
the settings are changed, poor
engine performance and damage
may result.
4.Remove the air filter element
from its guide and clean it with
solvent. After cleaning, remove
the remaining solvent by squeez-
ing the element.
5.Apply recommended oil to the
entire surface of the element and
squeeze out the excess oil. It
should be wet but not dripping.
1
2
1.Guide
2.Filter element
Recommended oil:
Engine oil
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b
a
1
EAU00632
Idle speed adjustment1.Start the engine and warm it up
for a few minutes at approxi-
mately 1,000 to 2,000 r/min.
Occasionally rev the engine to
4,000 to 5,000 r/min. The engine
is warm when it quickly responds
to the throttle.
2.Set the idle to the specified
engine speed by adjusting the
throttle stop screw. Turn the
screw in direction ato increase
engine speed and in direction b
to decrease engine speed.1.Throttle stop screw
NOTE:
If the specified idle speed cannot be
obtained by performing the above
adjustment, consult a Yamaha deal-
er.
Standard idle speed:
1,250 ~ 1,450 r/min
a
EAU00634
Throttle cable free play
adjustmentNOTE:
Before checking the throttle cable
free play, the engine idling speed
should be adjusted.Adjust the throttle cable by turning
the adjusting nut so that specified
free play at the throttle grip is
obtained.a.Free play
Free play:
3 ~ 5 mm
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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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