NOTE:
The fuel tank cap cannot be installed
unless the key is in the lock. In addi-
tion, the key cannot be removed if the
cap is not properly installed and loc-
ked.
EWA10120
s s
WARNING
Make sure that the fuel tank cap is
properly closed and locked before
riding.
EAU13220
Fuel
Make sure that there is sufficient fuel
in the tank. When refueling, be sure to
insert the pump nozzle into the fuel
tank filler hole and to fill the tank to
the bottom of the filler tube as shown.
1. Filing pipe
2. Fuel level
EWA10880
s s
WARNING
Do not overfill the fuel tank,
otherwise it may overflow
when the fuel warms up and
expands.
Avoid spilling fuel on the hot
engine.
ECA10070
CAUTION
Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since
fuel may deteriorate painted surfa-
ces or plastic parts.
EAU13320
Recommended fuel:
REGULAR UNLEADED GASOLINE
ONLY
Fuel tank capacity:
10,7 L (2,82 US gal) (2,35 Imp.gal)
Fuel reserve amount:
1,8 L (0,48 US gal) (0,40 Imp.gal)
ECA11400
CAUTION
Use only unleaded gasoline. The
use of leaded gasoline will cause
severe damage to internal engine
parts, such as the valves and piston
rings, as well as to the exhaust sys-
tem.
Your Yamaha engine has been desig-
ned to use regular unleaded gasoline
with a research octane number 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 maintenance
costs.
EAU13430
Catalytic converter
This model is equipped with a cataly-
tic converter in the exhaust chamber.
EWA10860
s s
WARNING
The exhaust system is hot after
operation. Make sure that the
exhaust system has cooled down
before doing any maintenance
work.
3
INSTRUMENT AND CONTROL FUNCTIONS
3-6
1
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1D0-F8199-E2.qxd 20/9/04 11:32 Página 20
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
1
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1D0-F8199-E2.qxd 20/9/04 11:32 Página 22
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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