engine YAMAHA DT125R 2000 Owner's Manual

1,000 km and beyondFull throttle can be used.
EC000053
cC8
8
Never let engine speeds enter
the red zone.
8 8
If any engine trouble should
occur during the break-in peri-
od, consult a Yamaha dealer
immediately.
EAU00458
ParkingWhen parking the motorcycle, stop
the engine and remove the ignition
key. Turn the fuel cock to ÒOFFÓ
whenever stopping the engine.
EW000058
wThe exhaust system is hot. Park
the motorcycle in a place where
pedestrians or children are not
likely to touch the motorcycle. Do
not park the motorcycle on a slope
or soft ground; the motorcycle
may overturn.
EC000062
cCNever park this motorcycle in an
area that would cause a fire haz-
zard such as grass or other materi-
als that may easily burn.
5-6
OPERATION AND IMPORTANT RIDING POINTS
1
2
3
45
6
7
8
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9
EAU03884
NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake service
9Regularly check and, if necessary, correct the brake fluid level.
9Every two years replace the internal components of the brake master cylinders and calipers, and change the
brake fluid.
9Replace the brake hoses every four years and if cracked or damaged.21
*Carburetor¥Check starter (choke) operation.
¥Adjust engine idling speed.ÖÖÖÖÖÖ
22*Autolube pump¥Check operation.
¥Bleed if necessary.ÖÖÖÖ
23Transmission oil¥Check oil level.ÖÖÖÖÖÖ
¥Change.ÖÖ
24*Cooling system¥Check coolant level and vehicle for coolant leakage.ÖÖÖÖÖ
¥Change.Every 3 years
25*Front and rear brake
switches¥Check operation.ÖÖÖÖÖÖ
26Moving parts and cables¥Lubricate.ÖÖÖÖÖ
27*Lights, signals and
switches¥Check operation.
¥Adjust headlight beam.ÖÖÖÖÖÖ NO.ITEMCHECK OR MAINTENANCE JOBODOMETER READING (´ 1,000 km)
ANNUAL
CHECK
16121824
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1
EAU01833
Spark plugRemoval
1.Remove the spark plug cap.2.Use the spark plug wrench in the
tool kit to remove the spark plug
as shown.Inspection
The spark plug is an important
engine component and is easy to
inspect. The condition of the spark
plug can indicate the condition of the
engine.
The ideal color on the white insulator
around the center electrode is a
medium-to-light tan color for a motor-
cycle that is being ridden normally.
Do not attempt to diagnose such
problems yourself. Instead, take the
motorcycle to a Yamaha dealer. You
should periodically remove and
inspect the spark plug because heat
and deposits will cause any spark
plug to slowly break down and erode.
If electrode erosion becomes exces-
sive, or if carbon and other deposits
are excessive, you should replace
the spark plug with the specified plug.1.Spark plug cap
Specified spark plug:
BR9ES (NGK)
BR8ES (NGK) (CH, A only)
1
1.Spark plug wrench
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9 Spark plug gap:
0.7 ~ 0.8 mm
Tightening torque:
Spark plug:
20 Nm (2.0 m
0kg)
1
3 2
EAU03109
Transmission oilOil level inspection
1.Place the motorcycle on a level
place and hold it in an upright
position. Warm up the engine for
several minutes.NOTE:
Be sure the motorcycle is positioned
straight up when checking the oil
level. A slight tilt toward the side can
result in false readings.1.Level window
2.Maximum level
3.Minimum level
Installation
1.Measure the electrode gap with
a wire thickness gauge and, if
necessary, adjust the gap to
specification.
2.Clean the gasket surface. Wipe
off any grime from the threads.
3.Install the spark plug and tighten
it to the specified torque.
1
1.Spark plug gap
NOTE:
If a torque wrench is not available
when you are installing a spark plug,
a good estimate of the correct torque
is 1/4 to 1/2 turn past finger tight.
Have the spark plug tightened to the
specified torque as soon as possible.4.Install the spark plug cap.
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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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