2006 YAMAHA DT125R engine

ECA10700
CAUTION
The following precautions must be
observed to prevent a fire hazard or
other damages.
Use only unleaded gasoline.
The use of leaded gasoline will
cause unrepairable damage to
the catalytic converter.
Never park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.
Do not allow the engine to idle
too long.
EAU13460
2-stroke engine oil
1. Oil tank cap
2. Sensor
Make 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.
Recommended oil:
Yamalube 2 or equivalent 2-stroke
engine oil (JASO grade “FC”, or ISO
grades “EG-C” or “EG-D”)
Oil quantity:
1,3 L (1,37 US qt) (0,29 Imp.qt)
EAU13560
Fuel cock
The fuel cock supplies fuel from the
tank to the carburetor while filtering it
also.
The fuel cock has three positions:OFF
1. Arrow mark
With the lever in this position, fuel will
not flow. Always return the lever to
this position when the engine is not
running.
ON
With the lever in this position, fuel
flows to the carburetor. Normal riding
is done with the lever in this position.
3
INSTRUMENT AND CONTROL FUNCTIONS
3-7
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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!
EAU13590
Starter (choke) lever “q”
1. Choke lever
Starting a cold engine requires a
richer air-fuel mixture, which is sup-
plied by the starter (choke).
Move the lever in direction (a) to turn
on the starter (choke).
Move the lever in direction (b) to turn
off the starter (choke).
EAU13960
Seat
To remove the seat
Remove the bolts, and then pull the
seat off.
1. Bolt (x2)
To install the seat
1. Insert the projections on the front
of the seat into the seat holders
as shown.
2. Place the seat in the original
position, and then tighten the
bolts.
NOTE:
Make sure that the seat is properly
secured before riding.
3
INSTRUMENT AND CONTROL FUNCTIONS
3-8
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EAU15090
Shock absorberEWA10220
s s
WARNING
This shock absorber contains
highly pressurized nitrogen gas.
For proper handling, read and
understand the following informa-
tion before handling the shock
absorber. The manufacturer cannot
be held responsible for property
damage or personal injury that may
result from improper handling.
Do not tamper with or attempt
to open the gas cylinder.
Do not subject the shock
absorber to an open flame or
other high heat sources, other-
wise it may explode due to
excessive gas pressure.
Do not deform or damage the
gas cylinder in any way, as this
will result in poor damping per-
formance.
Always have a Yamaha dealer
service the shock absorber.
EAU15250
YEIS handling precautions
1. YEIS
Improper installation of or damage to
any part of the YEIS (Yamaha Energy
Induction System) will result in poor
performance. Therefore, handle the
YEIS air chamber and air chamber
hose with special care and immedia-
tely replace any cracked or damaged
parts.
ECA10140
CAUTION
Do not attempt to modify the YEIS
in any way.
EAU15260
YPVS
1. YPVS
This 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 accor-
dance with the engine speed by a
computer-controlled servomotor.
Since the YPVS is an important part
of the engine and requires very sop-
histicated adjustment, have a Yamaha
dealer, who has the necessary profes-
sional knowledge and experience,
make this adjustment.
3
INSTRUMENT AND CONTROL FUNCTIONS
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ECA10150
CAUTION
The YPVS has been set and exten-
sively tested at the Yamaha factory.
Changing these settings without
sufficient technical knowledge may
result in poor performance of or
damage to the engine.
YPVS operation noises can be heard
in the following instances:
When the key is turned to “ON”
and the engine is started.
When the engine stalls with the
key in the “ON” position.
ECA10160
CAUTION
If the YPVS does not operate, have
a Yamaha dealer check it.
EAU15300
Sidestand
The sidestand is located on the left
side of the frame. Raise the sidestand
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
situations. (See further down for an
explanation of the ignition circuit cut-
off system.)
EWA10240
s s
WARNING
The vehicle must not be ridden with
the sidestand down, or if the sides-
tand cannot be properly moved up
(or does not stay up), otherwise the
sidestand could contact the ground
and distract the operator, resulting
in a possible loss of control. Yama-
ha’s ignition circuit cut-off system
has been designed to assist the
operator in fulfilling the responsibi-
lity of raising 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 pro-
perly.
EAU15311
Ignition circuit cut-off
system
The ignition circuit cut-off system
(comprising the sidestand switch,
clutch switch and neutral switch) has
the following functions.
It prevents starting when the
transmission is in gear and the
sidestand is up, but the clutch
lever is not pulled.
It prevents starting when the
transmission is in gear and the
clutch lever is pulled, but the
sidestand is still down.
It 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.
EWA10250
s s
WARNING
If a malfunction is noted, have a
Yamaha dealer check the system
before riding.
3
INSTRUMENT AND CONTROL FUNCTIONS
3-10
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NOTE:
This check is most reliable if performed with a warmed-up engine.
INSTRUMENT AND CONTROL FUNCTIONS
3-11
3
With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is turned on.
3. Turn the key on.
4. Shift the transmission into the neutral position.
5. Push the start switch.
Does the engine start?
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?
After the engine has stalled:
10. Move the sidestand up.
11. Keep the clutch lever pulled.
12. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can be ridden.
This check is most reliable if performed with
a warmed-up engine.
The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The sidestand switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The clutch switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
YES NO YES NO YES NO NOTE:
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PRE-OPERATION CHECKS
4-2
4
EAU15603
Pre-operation check list
ITEM CHECKS PAGE
• Check fuel level in fuel tank.
Fuel• Refuel if necessary.3-6
• Check fuel line for leakage.
• Check oil level in oil tank.
2-stroke engine oil• If necessary, add recommended oil to specified level. 3-7
• Check vehicle for oil leakage.
Transmission oil• Check oil level in transmission case.
6-7
• If necessary, add recommended oil to specified level.
• Check coolant level in reservoir.
Coolant• If necessary, add recommended coolant to specified level. 6-8
• Check cooling system for leakage.
• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
Front brake• Check brake pads for wear.
6-16/6-18
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add recommended brake fluid to specified level.
• Check hydraulic system for leakage.
• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
Rear brake• Check brake pads for wear.
6-16/6-18
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add recommended brake fluid to specified level.
• Check hydraulic system for leakage.
• Check operation.
Clutch• Lubricate cable if necessary.
6-15
• Check lever free play.
• Adjust if necessary.
• Make sure that operation is smooth.
Throttle grip• Check cable free play.
6-12/6-21
• If necessary, have Yamaha dealer adjust cable free play and lubricate
cable andgrip housing.
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Control cables• Make sure that operation is smooth.
6-21• Lubricate if necessary.
• Check chain slack.
Drive chain• Adjust if necessary.
6-19/6-20
• Check chain condition.
• Lubricate if necessary.
• Check for damage.
Wheels and tires• Check tire condition and tread depth.
6-13
• Check air pressure.
• Correct if necessary.
Brake and shift pedals• Make sure that operation is smooth.
6-21
• Lubricate pedal pivoting points if necessary.
Brake and clutch levers• Make sure that operation is smooth.
6-21
• Lubricate lever pivoting points if necessary.
Sidestand• Make sure that operation is smooth.
6-21
• Lubricate pivot if necessary.
Chassis fasteners• Make sure that all nuts, bolts and screws are properly tightened.
–
• Tighten if necessary.
Instruments, lights,• Check operation.
–
signals and switches• Correct if necessary.
Engine stop switch• Check operation.3-3
Sidestand switch• Check operation of ignition circuit cut-off system.
3-11
• If system is defective, have Yamaha dealer check vehicle.
PRE-OPERATION CHECKS
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EAU15950
EWA10270
s s
WARNING
Become 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 thoroughly
understand.
Never start the engine or ope-
rate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of cons-
ciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised comple-
tely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.
EAU16060
Starting a cold engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.
The transmission is in gear with
the clutch lever pulled and the
sidestand up.
EWA10290
s s
WARNING
Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-11.
Never 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 “f”.
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.
4. Turn the starter (choke) on and
completely close the throttle.
(See page 3-8.)
5. Start the engine by pushing the
start switch.
NOTE:
If the engine fails to start, release the
start switch, wait a few seconds, and
then try again. Each starting attempt
should be as short as possible to pre-
serve the battery. Do not crank the
engine more than 10 seconds on any
one attempt.
6. After starting the engine, move
the starter (choke) back halfway.
ECA11040
CAUTION
For maximum engine life, never
accelerate hard when the engine is
cold!
5
OPERATION AND IMPORTANT RIDING POINTS
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