2021 YAMAHA MT-125 turn signal

Table of contents
Battery ...........................................6-30
Replacing the fuses .......................6-31
Vehicle lights .................................6-32
Tail/brake light ...............................6-32
Replacing a turn signal light
bulb ............................................6-33
Replacing the license plate light bulb ............................................6-33
Supporting the motorcycle............6-34
Troubleshooting ............................6-34
Troubleshooting chart ...................6-35
Motorcycle care an d stora ge ..........7-1
Matte color caution .........................7-1
Care .................................................7-1
Storage ............................................7-3
Specifications ....................................8-1
Consumer information .....................9-1
Identification numbers .....................9-1
Diagnostic connector ......................9-2
Vehicle data recording ....................9-2
In dex ................................................10-1
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Safety information
1-2
1

Many accidents involve inexperi-
enced operators. In fact, many op-
erators who have been involved in
accidents do not even have a cur-
rent motorcycle license.
• Make sure that you are qualified and that you only lend your mo-
torcycle to other qualified oper-
ators.
• Know your skills and limits. Staying within your limits may
help you to avoid an accident.
• We recommend that you prac- tice riding your motorcycle
where there is no traffic until you
have become thoroughly famil-
iar with the motorcycle and all of
its controls.
 Many accidents have been
caused by error of the motorcycle
operator. A typical error made by
the operator is veering wide on a
turn due to excessive speed or un-
dercornering (insufficient lean an-
gle for the speed).
• Always obey the speed limit and never travel faster than warrant-
ed by road and traffic condi-
tions. • Always signal before turning or
changing lanes. Make sure that
other motorists can see you.
 The posture of the operator and
passenger is important for proper
control.
• The operator should keep both hands on the handlebar and
both feet on the operator foot-
rests during operation to main-
tain control of the motorcycle.
• The passenger should always hold onto the operator, the seat
strap or grab bar, if equipped,
with both hands and keep both
feet on the passenger footrests.
Never carry a passenger unless
he or she can firmly place both
feet on the passenger footrests.
 Never ride under the influence of
alcohol or other drugs.
 This motorcycle is designed for
on-road use only. It is not suitable
for off-road use. Protective Apparel
The majority of fatalities from motorcy-
cle accidents are the result of head in-
juries. The use of a safety helmet is the
single most critical factor in the pre-
vention or reduction of head injuries.
 Always wear an approved helmet.
 Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision that could delay seeing a
hazard.
 The use of a jacket, heavy boots,
trousers, gloves, etc., is effective
in preventing or reducing abra-
sions or lacerations.
 Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.
 Always wear protective clothing
that covers your legs, ankles, and
feet. The engine or exhaust sys-
tem become very hot during or af-
ter operation and can cause
burns.
 A passenger should also observe
the above precautions.
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Safety information
1-5
1operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
 Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires an d Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. See page 6-17
for tire specifications and for informa-
tion on servicing and replacing your
tires.
Transportin g the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle. 
Remove all loose items from the
motorcycle.
 Check that the fuel cock (if
equipped) is in the off position and
that there are no fuel leaks.
 Shift the transmission into gear
(for models with a manual trans-
mission).
 Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mounted
handlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
 The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Description
2-2
2
EAU10421
Right view
1
2
3
4
5
6
7
1. Rear turn signal lights (page 6-33)
2. Seat lock (page 3-19)
3. Front turn signal light (page 6-33)
4. Engine oil filter element (page 6-10)
5. Dipstick (page 6-10)
6. Brake pedal (page 3-14)
7. Rear brake fluid reservoir (page 6-22)UB6GE1E0.book Page 2 Thursday, July 30, 2020 1:08 PM

Instrument and control functions
3-2
3
To unlock the steering
From the “LOCK” position, push the
key and turn it to “OFF”.
EAU4939N
In
dicator li ghts an d warnin g
lig hts
EAU11022
Turn si gnal in dicator li ght “ ”
This indicator light flashes when a turn
signal light is flashing.
EAU11061
Neutral in dicator li ght “ ”
This indicator light comes on when the
transmission is in the neutral position.
EAU11081
Hi gh beam in dicator li ght “ ”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAU11449
Coolant temperature warnin g
li g ht “ ”
This warning light comes on when the
engine is overheating. If this occurs,
stop the engine immediately and allow
the engine to cool. (See page 6-36.)
For vehicles with a radiator fan, the ra-
diator fan(s) automatically switch on or
off according to the coolant tempera-
ture.TIPWhen the vehicle is turned on, the light
will come on for a few seconds, and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle. NOTICE
ECA10022
Do not continue to operate the en-
g ine if it is overheatin g.
1. Push.
2. Turn.12
1. Shift light
2. Turn signal indicator light “ ”
3. High beam indicator light “ ”
4. Anti-lock Brake System (ABS) warning
light “ ”
5. Malfunction indicator light “ ”
6. Coolant temperature warning light “ ”
7. Neutral indicator light “ ”ZAUM15665 6 7
2
3
4
1
ABS
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Instrument and control functions
3-12
3
for all six characters. After the
sixth character is set, all charac-
ters will flash twice and the setting
mode will automatically end.
Self-d iagnostic device
This model is equipped with a self-di-
agnostic device for various electrical
circuits.
If a problem is detected in any of those
circuits, the engine trouble warning
light will come on and the display will
indicate an error code.
If the display indicates any error codes,
note the code number, and then have
a Yamaha dealer check the vehicle.
NOTICE
ECA11591
If the display in dicates an error
co de, the vehicle shoul d b e checked
as soon as possi ble in or der to avoi d
en gine damag e.
EAU1234R
Handle bar switchesLeft
Ri ght
1. Self-diagnostic deviceZAUM1582
1
1. Pass switch “ ”
2. Dimmer switch “ / ”
3. Horn switch “ ”
4. Turn signal switch “ / ”
1. Start/Engine stop switch “ / / ”
12
3
4
1
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Instrument and control functions
3-13
3
EAU12352
Pass switch “ ”
Press this switch to flash the headlight.TIPWhen the dimmer switch is set
to “ ”, the passing switch has no ef-
fect.
EAU12402
Dimmer switch “ / ”
Set this switch to “ ” for the high
beam and to “ ” for the low beam.
EAU12461
Turn si gnal switch “ / ”
To signal a right-hand turn, push this
switch to “ ”. To signal a left-hand
turn, push this switch to “ ”. When
released, the switch returns to the cen-
ter position. To cancel the turn signal
lights, push the switch in after it has re-
turned to the center position.
EAU12501
Horn switch “ ”
Press this switch to sound the horn.
EAU68271
Start/En gine stop switch “ / / ”
To crank the engine with the starter,
set this switch to “ ”, and then slide
the switch toward “ ”. See page 5-2
for starting instructions prior to starting
the engine.
Set this switch to “ ” to stop the en-
gine in case of an emergency, such as
when the vehicle overturns or when the
throttle cable is stuck.
EAU12823
Clutch leverTo disengage the drivetrain from the
engine, such as when shifting gears,
pull the clutch lever toward to the han-
dlebar. Release the lever to engage the
clutch and transmit power to the rear
wheel.TIPThe lever should be pulled rapidly and
released slowly for smooth shifting.
(See page 5-3.)1. Clutch lever1
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Periodic maintenance an d a djustment
6-33
6
EAU62590
Replacin g a turn sig nal light
b ul b1. Remove the turn signal light lens
by removing the screw.
2. Remove the turn signal light bulb socket (together with the bulb) by
turning it counterclockwise. 3. Remove the burnt-out bulb by
pulling it out.
4. Insert a new bulb into the socket.
5. Install the socket (together with the bulb) by turning it clockwise.
6. Install the turn signal light lens by installing the screw. NOTICE: Do
not overti ghten the screw, oth-
erwise the lens may break.
[ECA11192] EAUM3510
Replacin
g the license plate
lig ht bul b1. Remove the license plate light unit
by removing the screw.
2. Remove the license plate light bulb socket (together with the
bulb) by pulling it out.
3. Remove the burnt-out bulb by pulling it out.
4. Insert a new bulb into the socket.
5. Install the socket (together with the bulb) by pushing it in.
6. Install the license plate light unit by installing the screw.
1. Screw
1
1. Turn signal light bulbZAUM1609
1
1. License plate light bulb socket
2. License plate light unit
3. ScrewZAUM1621
2
3
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