2002 YAMAHA DT125R light

5-2
OPERATION AND IMPORTANT RIDING POINTS
54. Turn the starter (choke) on and
completely close the throttle.
(See page 3-10 for starter
(choke) operation.)
5. Start the engine by pushing the
kickstarter lever down.
6. After starting the engine, move
the starter (choke) lever back
halfway.
ECA00045
cCFor maximum engine life, never
accelerate hard when the engine is
cold!7. When the engine is warm, turn
the starter (choke) off.NOTE:
The engine is warm when it responds
normally to the throttle with the starter
(choke) turned off.
EAU01258
Starting a warm engineFollow the same procedure as for
starting a cold engine with the excep-
tion that the starter (choke) is not
required when the engine is warm.
EAU00423
ShiftingShifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing
hills, etc.
The gear positions are shown in the
illustration.NOTE:
To shift the transmission into the neu-
tral position, press the shift pedal
down repeatedly until it reaches the
end of its travel, and then slightly
raise it.
6
5
4
3
2
1 N
1
1. Shift pedal
N. Neutral position
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5-3
OPERATION AND IMPORTANT RIDING POINTS
5
EC000048
cC8Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long
distances. The transmission is
properly lubricated only when
the engine is running.
Inadequate lubrication may
damage the transmission.
8Always use the clutch while
changing gears to avoid dam-
aging the engine, transmis-
sion, and drive train, which are
not designed to withstand the
shock of forced shifting.
EAU02937
Recommended shift points
(for Switzerland only)The recommended shift points during
acceleration are shown in the table
below.NOTE:
When shifting down two gears at a
time, reduce the speed accordingly
(e.g., down to 35 km/h when shifting
from 5th to 3rd gear).
EAU00424
Tips for reducing fuel
consumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Thoroughly warm up the engine.
8Turn the starter (choke) off as
soon as possible.
8Shift up swiftly, and avoid high
engine speeds during accelera-
tion.
8Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the
engine.
8Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad cross-
ings).
Shift point
(km/h)
1st→2nd
2nd→3rd
3rd→4th
4th→5th
5th→6th20
30
40
50
60
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6-4
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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.√√√√√ √
22*Autolube pump•Check operation.
•Bleed if necessary.√√√√
23 Transmission oil•Check oil level.√√√√√ √
•Change.√√
24*Cooling system•Check coolant level and vehicle for coolant leakage.√√√√ √
•Change.Every 3 years
25*Front and rear brake
switches•Check operation.√√√√√ √
26 Moving parts and cables•Lubricate.√√√√ √
27*Lights, signals and
switches•Check operation.
•Adjust headlight beam.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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6-9
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01833
Checking the spark plugThe spark plug is an important
engine component, which is easy to
check. Since heat and deposits will
cause any spark plug to slowly erode,
the spark plug should be removed
and checked in accordance with the
periodic maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
To remove the spark plug
1. Remove the spark plug cap.
1
1. Spark plug cap
To check the spark plug
1. Check that the porcelain insula-
tor around the center electrode
of the spark plug is a medium-to-
light tan (the ideal color when the
motorcycle is ridden normally).NOTE:
If the spark plug shows a distinctly
different color, the engine could be
defective. Do not attempt to diagnose
such problems yourself. Instead,
have a Yamaha dealer check the
motorcycle.2. Check the spark plug for elec-
trode erosion and excessive car-
bon or other deposits, and
replace it if necessary. 2. Remove the spark plug as
shown, with the spark plug
wrench included in the owner’s
tool kit.
1
1. Spark plug wrench
Specified spark plug:
BR9ES (NGK)
BR8ES (NGK) (CH, A only)
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6-10
PERIODIC MAINTENANCE AND MINOR REPAIR
6 To install the spark plug
1. Measure the spark plug gap with
a wire thickness gauge and, if
necessary, adjust the gap to
specification.
2. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then
tighten it to the specified torque.
a
a. Spark plug gap
EAU04272
Transmission oilThe transmission oil level should be
checked before each ride. In addition,
the transmission oil must be changed
at the intervals specified in the peri-
odic maintenance and lubrication
chart.
To check the transmission oil level
1. Place the motorcycle on a level
surface and hold it in an upright
position.NOTE:
Make sure that the motorcycle is
positioned straight up when checking
the oil level. A slight tilt to the side
can result in a false reading.2. Start the engine, warm it up for
several minutes, and then turn it
off.
NOTE:
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is
1/4–1/2 turn past finger tight.
However, the spark plug should be
tightened to the specified torque as
soon as possible.4. Install the spark plug cap.
Spark plug gap:
0.7–0.8 mmTightening torque:
Spark plug:
20 Nm (2.0 m0kgf)
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6-12
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EC000077
cC8In order to prevent clutch slip-
page (since the transmission
oil also lubricates the clutch),
do not mix any chemical addi-
tives with the oil.
8Make sure that no foreign
material enters the transmis-
sion.6. Start the engine, and then let it
idle for several minutes while
checking the transmission for oil
leakage. If oil is leaking, immedi-
ately turn off the engine and
check for the cause.
EAU01808
CoolantTo check the coolant level
1. Place the motorcycle on a level
surface and hold it in an upright
position.NOTE:
8The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
8Make sure that the motorcycle is
positioned straight up when
checking the coolant level. A
slight tilt to the side can result in
a false reading.
2. Remove panel A. (See page 6-8
for panel removal and installation
procedures.)
3. Check the coolant level in the
coolant reservoir.NOTE:
The coolant should be between the
minimum and maximum level marks.
2
1
1. Maximum level mark
2. Minimum level mark
Recommended transmission oil:
See page 8-1.
Oil quantity:
Periodic oil change:
0.75 L
Total amount (dry transmission):
0.8 L
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6-24
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EW000109
wA soft or spongy feeling in the
brake pedal can indicate the pres-
ence of air in the hydraulic system.
If there is air in the hydraulic sys-
tem, have a Yamaha dealer bleed
the system before operating the
motorcycle. Air in the hydraulic
system will diminish the braking
performance, which may result in
loss of control and an accident.
EAU00721
Checking the front and rear
brake padsThe front and rear brake pads must
be checked for wear at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU00713
Adjusting the rear brake light
switchThe rear brake light switch, which is
activated by the brake pedal, is prop-
erly adjusted when the brake light
comes on just before braking takes
effect. If necessary, adjust the brake
light switch as follows.
Turn the adjusting nut while holding
the rear brake light switch in place.
To make the brake light come on ear-
lier, turn the adjusting nut in direction
a. To make the brake light come on
later, turn the adjusting nut in direc-
tion b.
b
a 1
2
1. Brake light switch
2. Adjusting nut
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6-36
PERIODIC MAINTENANCE AND MINOR REPAIR
6 4. Remove the headlight bulb hold-
er by turning it counterclockwise,
and then remove the defective
bulb.
1
1. Headlight bulb holder
3. Disconnect the headlight cou-
pler, and then remove the head-
light bulb cover.
1
2
1. Headlight coupler
2. Headlight bulb cover
EAU01158
Replacing the headlight bulbIf the headlight bulb burns out,
replace it as follows.
1. Remove cowling A. (See page
6-5 for cowling removal and
installation procedures.)
2. Remove the headlight unit by
removing the bolts.
1
1. Bolt (×2)
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