2006 YAMAHA DT125R transmission

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
5-3
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ODOMETER READING (x 1000 Km) ANNUAL
CHECK
NoITEM CHECK OR MAINTENANCE JOB 1 6 12 18 24
22Transmission oil• Check oil level.√√ √ √√ √• Change.√√
23 *Cooling system• Check coolant level and vehicle for coolant leakage.√√√√ √• Change. Every 3 years
24 *Front and rear
• Check operation.√√ √ √√ √
brake switches
25Moving parts and cables• Lubricate.√√√√ √
Throttle grip • Check operation and free play.
26 * •Adjust the throttle cable free play if necessary.√√√√ √
housing and cable
• Lubricate the throttle grip housing and cable.
27 *Muffler and exhaust pipe• Check the screw clamp for looseness.√√ √ √√
28 *Lights, signals • Check operation.
and switches• Adjust headlight beam.√√ √ √√ √
PERIODIC MAINTENANCE AND MINOR REPAIR
6-4
6
EAU18670
NOTE:
The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinders and calipers, and change the bra-
ke fluid.
• Replace the brake hoses every four years and if cracked or damaged.
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Tightening torque:
Spark plug:
20 Nm (2 m•kgf)
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. Howe-
ver, the spark plug should be tighte-
ned to the specified torque as soon
as possible.
EAU19950
Transmission oil
1. Oil level window
2. Maximum level mark
3. Minimum level mark
The transmission oil level should be
checked before each ride. In addition,
the transmission oil must be changed
at the intervals specified in the perio-
dic maintenance and lubrication
chart.
To check the transmission oil level
1. Place the vehicle on a level surfa-
ce and hold it in an upright posi-
tion.
NOTE:
Make sure that the vehicle is positio-
ned straight up when checking the oil
level. A slight tilt to the side can result
in a false reading.
1. Plug to fill with oil
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil
settles, and then check the oil
level through the check window
located at the right side of the
crankcase.
NOTE:
The transmission oil should be at or
above the minimum level mark.
4. If the oil is below the minimum
level mark, remove the oil filler
cap, add sufficient oil of the
recommended type to raise it to
the correct level, and then install
and tighten the cap.
To change the transmission oil
1. Drain bolt
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
2
3
11
1
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1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the trans-
mission to collect the used oil.
3. Remove the oil filler cap and
drain bolt to drain the oil from the
transmission.
4. Install the transmission oil drain
bolt, and then tighten it to the
specified torque.
Tightening torque:
Transmission oil drain bolt:
15 Nm (1,5 m•kgf)
5. Add the specified amount of the
recommended transmission oil,
and then install and tighten the oil
filler cap.
Recommended transmission oil:
See page 8-1.
Oil change quantity:
0,8 L (0,85 US qt)
ECA10450
CAUTION
In order to prevent clutch slip-
page (since the transmission
oil also lubricates the clutch),
do not mix any chemical additi-
ves with the oil.
Make 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, imme-
diately turn off the engine and
check for the cause.
EAU20070
Coolant
The coolant level should be checked
before each ride. In addition, the coo-
lant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU20170
To check the coolant level
1. Place the vehicle on a level surfa-
ce and hold it in an upright posi-
tion.
NOTE:
The coolant level must be chec-
ked on a cold engine since the
level varies with engine tempera-
ture.
Make sure that the vehicle is
positioned straight up when
checking the coolant level. A
slight tilt to the side can result in
a false reading.
2. Remove panel D. (See page 6-6.)
3. Check the coolant level in the
coolant reservoir.
FULL
LOW
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
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Recommended brake fluid:
DOT 4
Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking performan-
ce.
Be careful that water does not
enter the brake fluid reservoir
when refilling. Water will signifi-
cantly lower the boiling point of
the fluid and may result in vapor
lock.
Brake fluid may deteriorate pain-
ted surfaces or plastic parts.
Always clean up spilled fluid
immediately.
As the brake pads wear, it is nor-
mal for the brake fluid level to
gradually go down. However, if
the brake fluid level goes down
suddenly, have a Yamaha dealer
check the cause.
EAU22730
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addi-
tion, have the oil seals of the master
cylinders and calipers as well as the
brake hoses replaced at the intervals
listed below or whenever they are
damaged or leaking.
Oil seals: Replace every two
years.
Brake hoses: Replace every four
years.
EAU22770
To check the drive chain slack
(a) Chain tension
1. Place the motorcycle on a level
surface and hold it in an upright
position.
NOTE:
When checking and adjusting the dri-
ve chain slack, the motorcycle should
be positioned straight up and there
should be no weight on it.
2. Shift the transmission into the
neutral position.
3. Move the rear wheel by pushing
the motorcycle to locate the tigh-
test portion of the drive chain,
and then measure the drive chain
slack as shown.
Drive chain slack:
45-55 mm (1,76-2,15 in)
4. If the drive chain slack is inco-
rrect, adjust it as follows.
6
PERIODIC MAINTENANCE AND MINOR REPAIR
6-19
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DimensionsOverall length
DT125RE 2210 mm
DT125X 2139 mm
Overall width
795 mm
Overall height
DT125RE 1200 mm
DT125X 1121 mm
Seat height
DT125RE 900 mm
DT125X 886 mm
Wheelbase
DT125RE 1415 mm
DT125X 1396 mm
Ground clearance
DT125RE 300 mm
DT125X 271 mm
Minimum turning radius
DT125RE 2100 mm
DT125X 2016 mm
WeightWith oil and fuel
DT125RE 126.0 kg
DT125X 134.0 kg
EngineEngine type
Liquid cooled 2-stroke
Cylinder arrangement
Forward-inclined single cylinder
Displacement
124.0 cm
3
Bore x stroke
56.0 x 50.7 mmCompression ratio
6.70 :1
Starting system
Electric starter
Lubrication system
Separate lubrication (Yamaha autolube)
Type
YAMALUBE 2-cycle oil or 2-stroke engine
oil (JASO FC g
Engine oil quantityQuantity
1.3 L
Transmission oilType
SAE10W30 type SE motor oil
Oil change quantity
0.75 L
Cooling systemCoolant reservoir capacity (up to the maxi-
mum leve
0.30 L
Radiator capacity (including all routes)
0.92 L
Air filterAir filter element
Wet element
FuelRecommended fuel
Regular unleaded gasoline only
Fuel tank capacity
10.7 L
Fuel reserve amount
1.8 L
CarburetorManufacturer
MIKUNI
Type x quantity
TM28-92 x1
Spark plug(s)Manufacturer/model
NGK/BR8ES
Spark plug gap
0.7-0.8 mm
Clutch type
Wet, multiple-disc
TransmissionPrimary reduction system
Helical gear
Primary reduction ratio
71/22 (3.227)
Secondary reduction system
Chain drive
Secondary reduction ratio
57/16 (3.563)
Transmission type
Constant mesh 6-speed
Operation
Left foot operation
Gear ratio1st
34/12 (2.833)
2nd
30/16 (1.875)
3rd
24/17 (1.412)
4th
24/21 (1.143)
8
SPECIFICATIONS
8-1
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AAdjusting the autolube pump ..................6-21
Adjusting the brake lever free play ..........6-16
Adjusting the brake pedal position and
free play .................................................6-17
Adjusting the clutch lever free play .........6-15
Adjusting the drive chain slack ................6-20
Adjusting the engine idling speed ...........6-12
Adjusting the rear brake light switch .......6-17
Ajusting the carburetor ............................6-11
Ajusting the throttle cable free play .........6-12
BBrake lever .................................................3-5
Brake pedal ................................................3-5
CCare............................................................7-1
Catalytic converter .....................................3-6
Changing the brake fluid..........................6-19
Checking and lubricating the brake and
shift pedals ............................................6-21
Checking and lubricating the breake and
clutch levers...........................................6-21
Checking and lubricating the cables .......6-21
Checking and lubricating the sidestand ..6-21
Checking and lubricating the throttle grip
and cable ...............................................6-21
Checking the drive chain slack ................6-19
Checking the front and rear brake
pads .......................................................6-18
Checking the front fork ............................6-22
Checking the spark plug ............................6-6
Checking the steering ..............................6-22
Checking the wheel bearings ..................6-23Cleaning the air filter element and check
hose .......................................................6-10
Clutch lever ................................................3-4
Controls and instruments ..........................2-3
Coolant.......................................................6-8
D2-stroke engine oil .....................................3-7
EEngine break-in ..........................................5-2
FFront wheel ..............................................6-26
Fuel cock....................................................3-7
Fuel tank cap .............................................3-5
H
Handlebar switches ...................................3-3
IIdentification numbers ...............................9-1
Ignition circuit cut-off system ..................3-10
Indicator and warning lights ......................3-2
LLeft view .....................................................2-1
Lubricating the drive chain ......................6-20
MMain switch/steering lock ..........................3-1
OOwner’s tool kit ..........................................6-1
PParking .......................................................5-3
Periodic maintenance and lubrication
chart .........................................................6-2
Pre-operation check list .............................4-2
RRear wheel ...............................................6-28Removing and installing cowlings and
panels ......................................................6-5
Replacing the fuse ...................................6-24
Replacing the headlight bulb ...................6-24
Replacing the tail/brake light bulb ...........6-25
Replacing the turn signal light bulb .........6-26
Right view ..................................................2-2
SSeat ............................................................3-8
Shift pedal ..................................................3-4
Shifting .......................................................5-2
Shock absorber..........................................3-9
Sidestand .................................................3-10
Specifications.............................................8-1
Speedometer unit ......................................3-3
Spoke wheels...........................................6-15
Starter (choke) lever ...................................3-8
Starting a cold engine ................................5-1
Starting a warm engine ..............................5-2
Storage.......................................................7-3
Supporting the motorcycle ......................6-26
TTires .........................................................6-13
Transmission oil .........................................6-7
Troubleshooting .......................................6-29
YYEIS handling precautions.........................3-9
YPVS ..........................................................3-9
INDEX
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