Page 12 of 94

3-1
EAU00027
INSTRUMENT AND CONTROL FUNCTIONS
3
EAU00029
Main switch/steering lockThe main switch/steering lock con-
trols the ignition and lighting systems,
and is used to lock the steering. The
various positions are described
below.
EAU00036
ON
All electrical systems are supplied
with power, and the engine can be
started. The key cannot be removed.
EAU00038
OFF
All electrical systems are off. The key
can be removed.
EAU00040
LOCK
The steering is locked, and all electri-
cal systems are off. The key can be
removed.
To lock the steering1. Turn the handlebars all the way
to the left.
2. Push the key in from the “OFF”
position, and then turn it to
“LOCK” while still pushing it.
3. Remove the key.
To unlock the steeringPush the key in, and then turn it to
“OFF” while still pushing it.
EW000016
wNever turn the key to “OFF” or
“LOCK” while the motorcycle is
moving, otherwise the electrical
systems will be switched off,
which may result in loss of control
or an accident. Make sure that the
motorcycle is stopped before turn-
ing the key to “OFF” or “LOCK”.
EAU01574
.
.
(Parking)
The steering is locked, and the tail-
lights and auxiliary lights are on, but
all other electrical systems are off.
The key can be removed.
The steering must be locked before
the key can be turned to “
.
”.
ECA00043
cCDo not use the parking position for
an extended length of time, other-
wise the battery may discharge.
OFFON
LOCKPPUSH
YM-8
IGNITION
ON
OFF
LOCK
PARKING
a
b
a. Push.
b. Turn.
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5-1
EAU00372
OPERATION AND IMPORTANT RIDING POINTS
5
EAU00373
w8Become 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 thorough-
ly understand.
8Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
8Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.
EAU04271
Starting a cold engineIn order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
8The transmission is in the neutral
position.
8The transmission is in gear with
the clutch lever pulled and the
sidestand up.
EW000054
w8Before starting the engine,
check the function of the igni-
tion circuit cut-off system
according to the procedure
described on page 3-17.
8Never 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 “#”.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 3-12 for starter
(choke) operation.)
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.
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5-4
OPERATION AND IMPORTANT RIDING POINTS
5
EAU00424
Tips for reducing fuel
consumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
8Thoroughly warm up the engine.
8Turn the starter (choke) off as
soon as possible.
8Shift up swiftly, and avoid high
engine speeds during accelera-
tion.
8Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the
engine.
8Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad cross-
ings).
EAU00436
Engine break-inThere is never a more important peri-
od in the life of your engine than the
period between 0 and 1,000 km. For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do
not put an excessive load on it for the
first 1,000 km. The various parts in
the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheat-
ing must be avoided.
EAU00453
0–500 km
8Avoid prolonged operation above
6,000 r/min.
8After every hour of operation,
stop the engine, and then let it
cool for five to ten minutes.
8Vary the engine speed from time
to time. Do not operate the
engine at one set throttle posi-
tion.
500–1,000 km
8Avoid prolonged operation
above 7,000 r/min.
8Rev the engine freely through
the gears, but do not use full
throttle at any time.
EC000060
cCAfter 1,000 km of operation, the
transmission oil must be changed.
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8-1
EAU01038
SPECIFICATIONS
8
Model TDR125
Dimensions
Overall length 2,120 mm
(F, GB, IRL, B, P, GR, E)
2,185 mm (S, SF, D, CH, A)
Overall width 840 mm
Overall height 1,295 mm
Seat height 850 mm
Wheel base 1,405 mm
Ground clearance 270 mm
Minimum turning radius 2,200 mm
Basic weight (with oil and full
fuel tank)135 kg
136 kg (CH, A)
Engine
Engine type Liquid cooled 2-stroke,
gasoline
Cylinder arrangement Forward inclined single
cylinder
Displacement 125 cm
3
Bore ×Stroke 56.0 ×50.7 mm
Compression ratio 6.6:1
Starting system Electric starter
Lubrication system Separate lubrication
(Yamaha Autolube)Engine oil (2-cycle)
Type Yamalube 2 or equivalent
2-stroke engine oil
Capacity
Total amount 1.2 L
Transmission oil
Type SAE 10W30 SE motor oil
Capacity
Periodic oil change 0.75 L
Total amount 0.8 L
Cooling system capacity
(total amount)1.05 L
Air filterWet type element
Fuel
Type REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity 11 L
Reserve amount 2.2 L
Carburetor
Manufacturer MIKUNI
Model ×quantity TM28SS ×1
Specifications
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