2018 YAMAHA MT-125 light

Table of contents
Safety information............................1-1
Description........................................2-1
Left view ..........................................2-1
Right view........................................2-2
Controls and instruments ................2-3
Instrument and control functions....3-1
Main switch/steering lock ...............3-1
Indicator lights and warning
lights ............................................3-2
Multi-function meter unit .................3-4
Handlebar switches.......................3-12
Clutch lever ...................................3-13
Shift pedal .....................................3-14
Brake lever ....................................3-14
Brake pedal ...................................3-15
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-17
Catalytic converter ........................3-18
Rider seat ......................................3-19
Sidestand ......................................3-20
Ignition circuit cut-off system........3-20
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Starting the engine ..........................5-2
Shifting ............................................5-3
Tips for reducing fuel
consumption ................................5-4
Engine break-in ...............................5-4
Parking ............................................5-5
Periodic maintenance and
adjustment........................................6-1
Owner’s tool kit ...............................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4
Removing and installing cowlings ...6-7
Checking the spark plug .................6-8Engine oil and oil filter element ....... 6-9
Coolant ......................................... 6-12
Replacing the air filter element
and cleaning the check hose..... 6-14
Checking the engine idling
speed......................................... 6-14
Adjusting the throttle grip free
play ............................................ 6-15
Valve clearance ............................. 6-16
Tires .............................................. 6-16
Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the front brake lever
free play ..................................... 6-20
Adjusting the brake pedal free
play ............................................ 6-21
Brake light switches ...................... 6-21
Checking the front and rear brake
pads........................................... 6-22
Checking the brake fluid level....... 6-23
Changing the brake fluid............... 6-24
Drive chain slack ........................... 6-24
Cleaning and lubricating the drive
chain .......................................... 6-26
Checking and lubricating the
cables ........................................ 6-26
Checking and lubricating the
throttle grip and cable ............... 6-27
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
brake pedal................................ 6-28
Checking and lubricating the
sidestand ................................... 6-28
Lubricating the swingarm
pivots ......................................... 6-29
Checking the front fork ................. 6-29
Checking the steering ................... 6-30
Checking the wheel bearings ....... 6-30
Battery .......................................... 6-31
Replacing the fuses ...................... 6-32
Replacing the headlight bulb ........ 6-33
Auxiliary lights ............................... 6-35
Tail/brake light .............................. 6-35
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Table of contents
Replacing a turn signal light
bulb ........................................... 6-36
Replacing the license plate light
bulb ........................................... 6-36
Supporting the motorcycle ........... 6-37
Troubleshooting............................ 6-37
Troubleshooting charts................. 6-38
Motorcycle care and storage.......... 7-1
Matte color caution ........................ 7-1
Care ................................................ 7-1
Storage ........................................... 7-4
Specifications................................... 8-1
Consumer information..................... 9-1
Identification numbers .................... 9-1
Diagnostic connectors.................... 9-2
Vehicle data recording.................... 9-2
Index................................................ 10-1
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Safety information
1-4
1sleeping bags, duffel bags, or
tents, can create unstable han-
dling or a slow steering re-
sponse.
This vehicle is not designed to
pull a trailer or to be attached to
a sidecar.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail-
able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Many companies with no connection
to Yamaha manufacture parts and ac-
cessories or offer other modifications
for Yamaha vehicles. Yamaha is not in
a position to test the products that
these aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer.
Aftermarket Parts, Accessories, and
Modifications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accesso-
ries or modifications are not suitable
because of potential safety hazards to
you or others. Installing aftermarket
products or having other modifications
performed to your vehicle that change
any of the vehicle’s design or operation
characteristics can put you and othersat greater risk of serious injury or
death. You are responsible for injuries
related to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.
Never install accessories or carry
cargo that would impair the per-
formance of your motorcycle.
Carefully inspect the accessory
before using it to make sure that it
does not in any way reduce
ground clearance or cornering
clearance, limit suspension travel,
steering travel or control opera-
tion, or obscure lights or reflec-
tors.
• Accessories fitted to the han-
dlebar or the front fork area can
create instability due to improp-
er weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
• Bulky or large accessories may
seriously affect the stability of
the motorcycle due to aerody-
namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become
unstable in cross winds. These
accessories may also cause in-
stability when passing or being
passed by large vehicles.
• Certain accessories can dis-
place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
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Safety information
1-5
1 operator 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 and 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. Refer to page
6-16 for tire specifications and more in-
formation on replacing your tires.
Transporting 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.
Point the front wheel straight
ahead on the trailer or in the truck
bed, and choke it in a rail to pre-
vent movement.
Shift the transmission in gear (for
models with a manual transmis-
sion).
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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Instrument and control functions
3-1
3
EAU10462
Main switch/steering lock
The main switch/steering lock controls
the ignition and lighting systems, and is
used to lock the steering. The various
positions are described below.
EAU36871ON
All electrical circuits are supplied with
power, the meter lighting, taillight, li-
cense plate light and auxiliary lights
come on, and the engine can be start-
ed. The key cannot be removed.
TIP
The headlight comes on automatically
when the engine is started and stays

even if the engine stalls.
EAU10662OFF
All electrical systems are off. The key
can be removed.
WARNING
EWA10062
Never turn the key to “OFF” or
“LOCK” while the vehicle is moving.
Otherwise the electrical systems will
be switched off, which may result in
loss of control or an accident.
EAU10696LOCK
The steering is locked and all electrical
systems are off. The key can be re-
moved.
To lock the steering
1. Turn the handlebars all the way to
the left or right.
2. With the key in the “OFF” position,
push the key in and turn it to
“LOCK”.
3. Remove the key.
TIP
If the steering will not lock, try turning
the handlebars back to the right or left
slightly.
To unlock the steering
1. Push.
2. Turn.
1. Push.
2. Turn.
12
12
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Instrument and control functions
3-2
3From the “LOCK” position, push the
key and turn it to “OFF”.
EAU49399
Indicator lights and warning
lights
EAU11022Turn signal indicator light “ ”
This indicator light flashes when a turn
signal light is flashing.
EAU11061Neutral indicator light “ ”
This indicator light comes on when the
transmission is in the neutral position.
EAU11081High beam indicator light “ ”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAU11341Fuel level warning light “ ”
This warning light comes on when the
fuel level drops below approximately
3.0 L (0.79 US gal, 0.66 Imp.gal). When
this occurs, refuel as soon as possible.
1. Turn signal indicator light “ ”
2. Neutral indicator light “ ”
3. High beam indicator light “ ”
4. Tachometer high-rpm warning light
5. Fuel level warning light “ ”
6. Engine trouble warning light “ ”
7. Anti-lock Brake System (ABS) warning
light “ ”
Lo
Hi
1/2
x1000r/min
ZAUM1316SELECTRESET
km/L/100kmMPGkm/h
MPH
ODOFTRIP12OILOIL
1235467
ABS
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Instrument and control functions
3-3
3 The electrical circuit of the warning
light can be checked according to the
following procedure.
1. Turn the key to “ON”.
2. If the warning light does not come
on, have a Yamaha dealer check
the electrical circuit.
EAU11486Engine trouble warning light “ ”
This warning light comes on if a prob-
lem is detected in the electrical circuit
monitoring the engine. If this occurs,
have a Yamaha dealer check the vehi-
cle.
The electrical circuit of the warning
light can be checked by turning the key
to “ON”. The warning light should
come on for a few seconds, and then
go off.
If the warning light does not come on
initially when the key is turned to “ON”,
or if the warning light remains on, have
a Yamaha dealer check the electrical
circuit.
EAU69890ABS warning light “ ”
In normal operation, the ABS warning
light comes on when the key is turned
to “ON”, and goes off after traveling at
a speed of 10 km/h (6 mi/h) or higher.
If the ABS warning light:
does not come on when the key is
turned to “ON”
comes on or flashes while riding
does not go off after traveling at a
speed of 10 km/h (6 mi/h) or high-
erThe ABS may not work correctly. If any
of the above occurs, have a Yamaha
dealer check the system as soon as
possible. (See page 3-15 for an expla-
nation of the ABS.)
WARNING
EWA16041
If the ABS warning light does not go
off after traveling at a speed of 10
km/h (6 mi/h) or higher, or if the
warning light comes on or flashes
while riding, the brake system re-
verts to conventional braking. If ei-
ther of the above occurs, or if the
warning light does not come on at
all, use extra caution to avoid possi-
ble wheel lock during emergency
braking. Have a Yamaha dealer
check the brake system and electri-
cal circuits as soon as possible.
EAUM3440Tachometer high-rpm warning light
This light flashes at 9500 r/min to warn
you that the engine speed is about to
enter the high-rpm zone. Once the en-
gine speed reaches 10000 r/min, this
light will come on to warn you that it is
necessary to shift up to avoid engine
damage.
To activate or deactivate the tachome-
ter high-rpm warning light, hold the
“INFO” button pushed, turn the key to
“ON”, and when the tachometer high-
rpm warning light starts flashing, press
the “SELECT” button.
TIP
When activating or deactivating the
warning light the function, after press-

ABS
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Instrument and control functions
3-4
3come on to indicate that the function is
activated or the light will go off to indi-
cate that the function is deactivated.
EAUM3423
Multi-function meter unit
TIP
When the key is turned to “ON”, all
display segments of the multi-
function meter unit will momen-
tarily appear in order to test the
electrical circuit. The speedome-
ter, tachometer, fuel meter and
coolant temperature meter will
then perform a display check and
a welcome message will scroll
across the multi-function display.
1. “INFO” switch
2. “RESET” button
3. “SELECT” button
1. Coolant temperature meter
2. Tachometer
3. Fuel meter
4. Odometer/tripmeter/fuel reserve tripmeter
5. Clock
6. Speedometer
7. Multi-function display
Lo1/2ODO
ZAUM1299
SELECTRESET
INFO
km/L/100kmMPGkm/h
MPH
ODOFTRIPx1000r/minOILOIL
23
1
Lo
Hi
1/2
x1000r/min
ZAUM1464
km/h
ODOOIL
123
4567
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