2002 YAMAHA DT125R engine

3-7
INSTRUMENT AND CONTROL FUNCTIONS
3
EW000130
w8Do not overfill the fuel tank,
otherwise it may overflow
when the fuel warms up and
expands.
8Avoid spilling fuel on the hot
engine.
EAU00185
cCImmediately wipe off spilled fuel
with a clean, dry, soft cloth, since
fuel may deteriorate painted sur-
faces or plastic parts.
EAU04206
Your Yamaha engine has been
designed to use regular unleaded
gasoline with a research octane num-
ber of 91 or higher. If knocking (or
pinging) occurs, use a gasoline of a
different brand or premium unleaded
fuel. Use of unleaded fuel will extend
spark plug life and reduce mainte-
nance costs.
EAU01084
Catalytic converter(for Switzerland and Austria)
This motorcycle is equipped with a
catalytic converter in the exhaust
chamber.
EW000128
wThe exhaust system is hot after
operation. Make sure that the
exhaust system has cooled down
before doing any maintenance
work.
Recommended fuel:
REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity:
Total amount:
10.0 L
Reserve amount:
1.8 L
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3-8
INSTRUMENT AND CONTROL FUNCTIONS
3
EC000114
cCThe following precautions must be
observed to prevent a fire hazard
or other damages.
8Use only unleaded gasoline.
The use of leaded gasoline will
cause unrepairable damage to
the catalytic converter.
8Never park the motorcycle
near possible fire hazards
such as grass or other materi-
als that easily burn.
8Do not allow the engine to idle
too long.
EAU03750
2-stroke engine oilMake sure that there is sufficient oil in
the 2-stroke engine oil tank. Add the
recommended 2-stroke engine oil if
necessary.NOTE:
Make sure that the 2-stroke engine
oil tank cap is properly installed.
21
1. 2-stroke engine oil tank cap
2. Stopper
Recommended oil:
Yamalube 2 or equivalent
2-stroke engine oil (JASO
grade “FC”, or ISO grades
or “EG-D”)
Oil quantity:
1.2 L
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3-9
INSTRUMENT AND CONTROL FUNCTIONS
3
ON
With the lever in this position, fuel
flows to the carburetor. Normal riding
is done with the lever in this position.
ON
FUEL
RES
OFF
1
ON
1. Arrow mark positioned over “ON”
RES
This indicates reserve. If you run out
of fuel while riding, move the lever to
this position. Fill the tank at the first
opportunity. Be sure to set the lever
back to “ON” after refueling!
OFF
ONFUEL RES
1
RES
1. Arrow mark positioned over “RES”
EAU03050
Fuel cockThe fuel cock supplies fuel from the
tank to the carburetor while filtering it
also.
The fuel cock has three positions:
OFF
With the lever in this position, fuel will
not flow. Always return the lever to
this position when the engine is not
running.
RES
ONFUEL
OFF
1
1. Arrow mark positioned over “OFF”OFF: closed position
RES: reserve position
ON: normal position
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3-10
INSTRUMENT AND CONTROL FUNCTIONS
3
EAU03839
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”
EAU00212
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
EAU02934
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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3-14
INSTRUMENT AND CONTROL FUNCTIONS
3
EAU00320
Carrier
EW000032
w8Do not exceed the load limit of
2 kg for the carrier.
8Do not exceed the maximum
load of 180 kg/178 kg (for CH,
A) for the vehicle.
1
1. Carrier
EAU00325
YEIS handling precautions Improper installation of or damage to
any part of the YEIS (Yamaha
Energy Induction System) will result
in poor performance. Therefore, han-
dle the YEIS air chamber and air
chamber hose with special care and
immediately replace any cracked or
damaged parts.
EC000022
cCDo not attempt to modify the YEIS
in any way.
12
1. YEIS air chamber
2. Air chamber hose
EAU00326
YPVSThis model is equipped with the
YPVS (Yamaha Power Valve
System). This system boosts engine
performance and efficiency by means
of a variable valve in the exhaust
port. The YPVS valve is constantly
adjusted in accordance with the
engine speed by a computer-con-
trolled servomotor.
Since the YPVS is an important part
of the engine and requires very
sophisticated adjustment, have a
Yamaha dealer, who has the neces-
sary professional knowledge and
experience, make this adjustment.
1
1. YPVS
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3-15
INSTRUMENT AND CONTROL FUNCTIONS
3
EC000023
cCThe YPVS has been set and exten-
sively tested at the Yamaha facto-
ry. Changing these settings with-
out sufficient technical knowledge
may result in poor performance of
or damage to the engine.YPVS operation noises can be heard
in the following instances:
8When the key is turned to “ON”
and the engine is started.
8When the engine stalls with the
key in the “ON” position.
EC000024
cCIf the YPVS does not operate, have
a Yamaha dealer check it.
EAU00330
SidestandThe sidestand is located on the left
side of the frame. Raise the side-
stand or lower it with your foot while
holding the motorcycle upright.NOTE:
The built-in sidestand switch is part of
the ignition circuit cut-off system,
which cuts the ignition in certain situ-
ations. (See further down for an
explanation of the ignition circuit cut-
off system.)
EW000044
wThe motorcycle must not be ridden
with the sidestand down, or if the
sidestand cannot be properly
moved up (or does not stay up),
otherwise the sidestand could con-
tact the ground and distract the
operator, resulting in a possible
loss of control. Yamaha’s ignition
circuit cut-off system has been
designed to assist the operator in
fulfilling the responsibility of rais-
ing the sidestand before starting
off. Therefore, check this system
regularly as described below and
have a Yamaha dealer repair it if it
does not function properly.
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3-16
EAU03571
Ignition circuit cut-off
systemThe ignition circuit cut-off system
(comprising the sidestand switch and
neutral switch) has the following func-
tions.
8It prevents starting when the
transmission is in gear and the
sidestand is still down.
8It cuts the running engine when
the transmission is in gear and
the sidestand is moved down.
Periodically check the operation of
the ignition circuit cut-off system
according to the following procedure.
EW000045
wIf a malfunction is noted, have a
Yamaha dealer check the system
before riding.INSTRUMENT AND CONTROL FUNCTIONS
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3-17
INSTRUMENT AND CONTROL FUNCTIONS
3
With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is set to “
#”.
3. Turn the key to “ON”.
4. Shift the transmission into the neutral position.
5. Push the kickstarter lever down.
Does the engine start?
The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
The sidestand switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
NO
NOTE:This check is most reliable if performed with
a warmed-up engine.
YESYES NO
The system is OK. The motorcycle can be ridden.
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