2002 YAMAHA DT125R fuel

3-10
INSTRUMENT AND CONTROL FUNCTIONS
3
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Starter (choke) lever“1”Starting a cold engine requires a rich-
er air-fuel mixture, which is supplied
by the starter (choke).
Move the lever in direction ato turn
on the starter (choke).
Move the lever in direction bto turn
off the starter (choke).
a
b
1
1. Starter (choke) lever “1”
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KickstarterTo start the engine, fold out the kick-
starter lever, move it down lightly with
your foot until the gears engage, and
then push it down smoothly but force-
fully. This model is equipped with a
primary kickstarter, allowing the
engine to be started in any gear if the
clutch is disengaged. However, shift-
ing the transmission into the neutral
position before starting is recom-
mended.
1
1. Kickstarter
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Steering lockTo lock the steering
1. Turn the handlebar all the way to
the right.
2. Open the steering lock cover,
and then insert the key.
3. Turn the key 1/8 turn counter-
clockwise, push it in while turning
the handlebar slightly to the left,
and then turn the key 1/8 turn
clockwise.
4. Check that the steering is locked,
remove the key, and then close
the lock cover.
2
1
1. Steering lock cover
2. Steering lock
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4-1
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PRE-OPERATION CHECKS
4The condition of a vehicle is the owner’s responsibility. Vital components can start to deteriorate quickly and unexpect-
edly, even if the vehicle remains unused (for example, as a result of exposure to the elements). Any damage, fluid leak-
age or loss of tire air pressure could have serious consequences. Therefore, it is very important, in addition to a thor-
ough visual inspection, to check the following points before each ride.
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Pre-operation check list
ITEM CHECKS PAGE
Fuel•Check fuel level in fuel tank.
•Refuel if necessary.
•Check fuel line for leakage.3-5–3-7
2-stroke engine oil•Check oil level in oil tank.
•If necessary, add recommended oil to specified level.
•Check vehicle for oil leakage.3-8
Transmission oil•Check oil level in transmission case.
•If necessary, add recommended oil to specified level.6-10–6-12
Coolant•Check coolant level in reservoir.
•If necessary, add recommended coolant to specified level.
•Check cooling system for leakage.6-12–6-15
Front brake•Check operation.
•If soft or spongy, have Yamaha dealer bleed hydraulic system.
•Check lever free play.
•Adjust if necessary.
•Check fluid level in reservoir.
•If necessary, add recommended brake fluid to specified level.
•Check hydraulic system for leakage.3-5, 6-23, 6-24–6-26
Rear brake•Check operation.
•If soft or spongy, have Yamaha dealer bleed hydraulic system.
•Check fluid level in reservoir.
•If necessary, add recommended brake fluid to specified level.
•Check hydraulic system for leakage.3-5, 6-23–6-26
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5-1
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OPERATION AND IMPORTANT RIDING POINTS
5
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w8Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer
regarding any control or func-
tion that you do not thorough-
ly understand.
8Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
8Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.
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Starting a cold engineIn order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
8The transmission is in the neutral
position.
8The transmission is in gear with
the clutch lever pulled and the
sidestand up.
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w8Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-17.
8Never ride with the sidestand
down.
1. Turn the fuel cock lever to “ON”.
2. Turn the key to “ON” and make
sure that the engine stop switch
is set to “#”.
3. Shift the transmission into the
neutral position.NOTE:
When the transmission is in the neu-
tral position, the neutral indicator light
should be on, otherwise have a
Yamaha dealer check the electrical
circuit.
ON
FUEL
RES
OFF
1
ON
1. Arrow mark positioned over “ON”
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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.
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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).
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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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5-5
OPERATION AND IMPORTANT RIDING POINTS
5
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ParkingWhen parking, stop the engine,
remove the key from the main switch,
and then turn the fuel cock lever to
“OFF”.
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w8Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely
to touch them.
8Do not park on a slope or on
soft ground, otherwise the
motorcycle may overturn.
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cCNever park in an area where there
are fire hazards such as grass or
other flammable materials.
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6-2
PERIODIC MAINTENANCE AND MINOR REPAIR
6
NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1,000 km)
ANNUAL
CHECK
1 6 12 18 24
1
*Fuel line•Check fuel hoses for cracks or damage.√√√√ √
2 Spark plug•Replace.√√√√ √
3 Air filter element•Clean.√√
•Replace.√√
4*Battery•Check electrolyte level and specific gravity.
•Make sure that the breather hose is properly routed.√√√√ √
5 Clutch•Check operation.
•Adjust.√√√√√
6*Front brake•Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√√√√ √
•Replace brake pads.Whenever worn to the limit
7*Rear brake•Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√√√√ √
•Replace brake pads.Whenever worn to the limit
8*Brake hoses•Check for cracks or damage.√√√√ √
•Replace. (See NOTE on page 6-4.)Every 4 years
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Periodic maintenance and lubrication chart
NOTE:
8The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.
8From 30,000 km, repeat the maintenance intervals starting from 6,000 km.
8Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and
technical skills.
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6-43
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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TroubleshootingAlthough Yamaha motorcycles
receive a thorough inspection before
shipment from the factory, trouble
may occur during operation. Any
problem in the fuel, compression, or
ignition systems, for example, can
cause poor starting and loss of
power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcy-
cle require any repair, take it to a
Yamaha dealer, whose skilled techni-
cians have the necessary tools,
experience, and know-how to service
the motorcycle properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life
and can lead to expensive repair
bills.
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To install the rear wheel
1. Install the drive chain onto the
rear sprocket, and then insert the
wheel axle from the left side.NOTE:
Make sure that there is enough
space between the brake pads
before inserting the brake disc
between the pads.2. Install the swingarm end bolts,
and then lower the rear wheel so
that it is on the ground.
3. Adjust the drive chain slack.
(See page 6-27 for drive chain
slack adjustment procedures.)
4. Tighten the axle nut and
swingarm end bolts to the speci-
fied torques.
Tightening torques:
Axle nut:
90 Nm (9.0 m0kgf)
Swingarm end bolts:
3 Nm (0.3 m0kgf)
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6-44
PERIODIC MAINTENANCE AND MINOR REPAIR
6
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 kickstarter.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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Troubleshooting charts
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wKeep away open flames and do not smoke while checking or working on the fuel system.
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