2018 YAMAHA MT-125 transmission

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
3-2
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
UBR3E1E0.book Page 2 Wednesday, August 10, 2016 9:45 AM

Instrument and control functions
3-14
3
EAU12872
Shift pedal
The shift pedal is located on the left
side of the motorcycle and is used in
combination with the clutch lever when
shifting the gears of the 6-speed con-
stant-mesh transmission equipped on
this motorcycle.
EAU12892
Brake lever
The brake lever is located on the right
side of the handlebar. To apply the
front brake, pull the lever toward the
throttle grip.
1. Shift pedal
ZAUM1200
1. Brake lever
ZAUM1201
1
I
NFO
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Instrument and control functions
3-20
3
EAU15306
Sidestand
The sidestand is located on the left
side of the frame. Raise the sidestand
or lower it with your foot while holding
the vehicle upright.
TIP
The built-in sidestand switch is part of
the ignition circuit cut-off system,
which cuts the ignition in certain situa-
tions. (See the following section for an
explanation of the ignition circuit cut-
off system.)
WARNING
EWA10242
The vehicle must not be ridden with
the sidestand down, or if the side-
stand cannot be properly moved up
(or does not stay up), otherwise the
sidestand could contact the ground
and distract the operator, resulting
in a possible loss of control.
Yamaha’s ignition circuit cut-off
system has been designed to assist
the operator in fulfilling the respon-
sibility of raising the sidestand be-
fore starting off. Therefore, check
this system regularly and have a
Yamaha dealer repair it if it does not
function properly.
EAU66730
Ignition circuit cut-off system
The ignition circuit cut-off system
(comprising the sidestand switch,
clutch switch and neutral switch) has
the following functions.
It prevents starting when the
transmission is in gear and the
sidestand is up, but the clutch le-
ver is not pulled.
It prevents starting when the
transmission is in gear and the
clutch lever is pulled, but the side-
stand is still down.
It cuts the running engine when
the transmission is in gear and the
sidestand is moved down.
Periodically check the operation of the
ignition circuit cut-off system accord-
ing to the following procedure.
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Instrument and control functions
3-21
3
With the engine turned off:
1. Move the sidestand down.
2.
Make sure that the engine stop switch
is set to “ ”.
3. Turn the key on.
4. Shift the transmission into the neutral
position.
5. Push the start switch.
Does the engine start?
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
10. Move the sidestand up.
11. Keep the clutch lever pulled.
12. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can
be ridden.
The neutral switch may not be working
correctly.
The motorcycle should not be ridden
until checked by a Yamaha dealer.
The sidestand switch may not be
working correctly.
The motorcycle should not be ridden
until checked by a Yamaha dealer.
The clutch switch may not be working
correctly.
The motorcycle should not be ridden
until checked by a Yamaha dealer.
WARNING
If a malfunction is noted, have a
Yamaha dealer check the system
before riding.
YES NO
YES NO
YES NO
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Operation and important riding points
5-2
5
EAUM3531
Starting the engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.
The transmission is in gear with
the clutch lever pulled and the
sidestand up.
See page 3-20 for more informa-
tion.
1. Turn the key to “ON” and make
sure that the engine stop switch is
set to “ ”.
The following warning lights and
indicator lights should come on for
a few seconds, then go off.
Neutral indicator light
Turn signal indicator light
High beam indicator light
Engine trouble warning light
Fuel level warning light
Tachometer high-rpm warn-
ing light
NOTICE
ECA11834
If a warning or indicator light does
not come on initially when the key is
turned to “ON”, or if a warning or in-
dicator light remains on, see page
3-2 for the corresponding warning
and indicator light circuit check.
The ABS warning light should
come on when the key is turned to
“ON”, and then go off after travel-
ing at a speed of 10 km/h (6 mi/h)
or higher.
NOTICE
ECA17682
If the ABS warning light does not
come on and then go off as ex-
plained above, see page 3-2 for the
warning light circuit check.
2. Shift the transmission into the
neutral position. The neutral indi-
cator light should come on. If not,
ask a Yamaha dealer to check the
electrical circuit.
3. Start the engine by pushing the
start switch.
If the engine fails to start, release
the start switch, wait a few sec-
onds, and then try again. Each
starting attempt should be as
short as possible to preserve the
battery. Do not crank the engine
more than 10 seconds on any one
attempt.
NOTICE
ECA11043
For maximum engine life, never ac-
celerate hard when the engine is
cold!
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Operation and important riding points
5-3
5
EAU16673
Shifting
Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing hills,
etc.
The gear positions are shown in the il-
lustration.
TIP
To shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of its
travel, and then slightly raise it.
NOTICE
ECA10261
Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long dis-
tances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.
Always use the clutch while
changing gears to avoid dam-
aging the engine, transmission,and drive train, which are not
designed to withstand the
shock of forced shifting.
1. Shift pedal
2. Neutral position
ZAUM1203
1 N2 3 4 5
6
12
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Periodic maintenance and adjustment
6-24
6
EAU22733
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, 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.
EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAUM3551To check the drive chain slack
1. Place the motorcycle on the side-
stand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
2. Shift the transmission into the
neutral position.
3. Measure the drive chain slack at
the arrow mark on the swingarm
as shown in the illustration.
4. If the drive chain slack is incorrect,
adjust it as follows.
EAU3431ATo adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.
1. Loosen the axle nut and the lock-
nut on each side of the swingarm.
Drive chain slack:
35.0–45.0 mm (1.38–1.77 in)
1. Drive chain slack
ZAUM1233
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