engine YAMAHA DT125R 2005 User Guide

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
3-9
1
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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
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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
4-3
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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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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.
EAU16640
Starting a warm engine
Follow 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.
EAU16671
Shifting
Shifting 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.
N. Neutral
1. Shift pedal
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.
ECA10260
CAUTION
Even 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. Inade-
quate lubrication may damage
the transmission.
Always use the clutch while
changing gears to avoid dama-
ging the engine, transmission,
and drive train, which are not
designed to withstand the
shock of forced shifting.
EAU16830
Engine break-in
There is never a more important
period in the life of your engine than
the period between 0 and 1000 km
(600 mi). For this reason, you should
read the following material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1000 km (600 mi). The various parts in
the engine wear and polish themsel-
ves to the correct operating clearan-
ces. During this period, prolonged
full-throttle operation or any condition
that might result in engine overhea-
ting must be avoided.
EAU17150
0–150 km (0–90 mi)
Avoid prolonged operation above 1/3
throttle.
5
OPERATION AND IMPORTANT RIDING POINTS
5-2
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After every hour of operation, stop the
engine, and then let it cool for five to
ten minutes.
Vary the engine speed from time to
time. Do not operate the engine at
one set throttle position.
150–500 km (90–300 mi)
Avoid prolonged operation above 1/2
throttle.
Rev the engine freely through the
gears, but do not use full throttle at
any time.
500–1000 km (300–600 mi)
Avoid prolonged operation above 3/4
throttle.
ECA10370
CAUTION
After 1000 km (600 mi) of operation,
the transmission oil must be chan-
ged.
1000 km (600 mi) and beyond
Avoid prolonged full-throttle opera-
tion. Vary the engine speed occasio-
nally.
ECA10270
CAUTION
If any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealer
check the vehicle.
EAU17180
Parking
When parking, stop the engine, remo-
ve the key from the main switch, and
then turn the fuel cock lever to “OFF”.
EWA10310
s s
WARNING
Since the engine and exhaust
system can become very hot,
park in a place where pedes-
trians or children are not likely
to touch them.
Do not park on a slope or on
soft ground, otherwise the
vehicle may overturn.
ECA10380
CAUTION
Never park in an area where there
are fire hazards such as grass or
other flammable materials.
5
OPERATION AND IMPORTANT RIDING POINTS
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ODOMETER READING (x 1000 Km) ANNUAL
CHECK
NoITEM CHECK OR MAINTENANCE JOB 1 6 12 18 24
9*Tires• Check tread depth and for damage.
• Replace if necessary.
• Check air pressure.√√√√ √
• Correct if necessary.
10 *Wheel bearings• Check bearing for looseness or damage.√√√√
11 *Swingarm• Check operation and for excessive play.√√√√• Lubricate with lithium-soap-based grease. Every 24000 km
• Check chain slack, alignment and condition.
12Drive chain• Adjust and lubricate chain with a special O-ring chain Every 500 km and after washing the
lubricant thoroughly.motorcycle or riding in the rain
13 *Steering bearings• Check bearing play and steering for roughness.√√ √ √√• Lubricate with lithium-soap-based grease. Every 50000 km
14 *Chassis fasteners• Make sure that all nuts, bolts and screws
√√√√ √
are properly tightened.
15Sidestand• Check operation.
• Lubricate.√√√√ √
16 *Sidestand switch• Check operation.√√ √ √√ √
17 *Front fork• Check operation and for oil leakage.√√√√
18 *Shock absorber assembly•Check operation and shock absorber for oil leakage.√√√√
Rear suspension relay • Check operation.√√√√
19 *arm and connecting arm
• Lubricate with lithium-soap-based grease.
√√
pivoting points
20 *Carburetor• Check starter (choke) operation.
• Adjust engine idling speed.√√ √ √√ √
21 *Autolube pump• Check operation.
• Bleed if necessary.√√√√
PERIODIC MAINTENANCE AND MINOR REPAIR
6-3
6
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EAU19292
Panels D and E
1. Screw
To remove one of the panels
Remove the screw, and then pull the
panel off as shown.
T
o install the panel
Place the panel in the original posi-
tion, and then install the screw.
EAU19620
Checking the spark plug
1. Spark plug inspection
The spark plug is an important engine
component, which should be chec-
ked periodically, preferably by a
Yamaha dealer. Since heat and depo-
sits will cause any spark plug to
slowly erode, it 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.The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally). 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 vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon
or other deposits, it should be repla-
ced.
Specified spark plug:
BR8ES (NGK)
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
Spark plug gap:
0,7-0,8 mm (0,0276-0,0315 in)
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
6
PERIODIC MAINTENANCE AND MINOR REPAIR
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