2000 YAMAHA DT125R check engine

6-11
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
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.
3MB-9-E7 12/27/00 2:52 PM Page 47

6-12
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
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
3MB-9-E7 12/27/00 2:52 PM Page 48

6-13
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
9
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
3MB-9-E7 12/27/00 2:52 PM Page 49

6-15
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
9
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.
3MB-9-E7 12/27/00 2:52 PM Page 51

6-17
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
9
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
3MB-9-E7 12/27/00 2:52 PM Page 53

6-29
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
9
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.
3MB-9-E7 12/27/00 2:52 PM Page 65

6-36
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
9
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.
3MB-9-E7 12/27/00 2:52 PM Page 72

6-38
PERIODIC MAINTENANCE AND MINOR REPAIR
1
2
3
4
56
7
8
9
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
3MB-9-E7 12/27/00 2:52 PM Page 74