2020 YAMAHA MT-125 ignition

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 .....................................3-13
Brake lever ....................................3-14
Brake pedal ...................................3-14
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-16
Fuel tank overflow hose ................3-18
Catalytic converter ........................3-18
Seat ...............................................3-19
Helmet holder ................................3-20
Sidestand ......................................3-20
Ignition circuit cut-off system........3-21
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Engine break-in ...............................5-1
Starting the engine ..........................5-2
Shifting ............................................5-4
Tips for reducing fuel
consumption ................................5-5
Parking ............................................5-6
Periodic maintenance and
adjustment........................................6-1
Tool kit.............................................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4Removing and installing
cowlings ...................................... 6-7
Checking the spark plug ................. 6-7
Engine oil and oil filter element ....... 6-8
Why Yamalube .............................. 6-11
Coolant ......................................... 6-11
Replacing the air filter element
and cleaning the check hose..... 6-13
Adjusting the engine idling
speed......................................... 6-13
Adjusting the throttle grip free
play ............................................ 6-14
Valve clearance ............................. 6-15
Tires .............................................. 6-15
Cast wheels .................................. 6-18
Adjusting the clutch lever free
play ............................................ 6-18
Checking the front brake lever
free play ..................................... 6-19
Adjusting the brake pedal free
play ............................................ 6-20
Brake light switches ...................... 6-20
Checking the front and rear brake
pads........................................... 6-21
Checking the brake fluid level....... 6-22
Changing the brake fluid............... 6-23
Drive chain slack ........................... 6-23
Cleaning and lubricating the drive
chain .......................................... 6-25
Checking and lubricating the
cables ........................................ 6-25
Checking and lubricating the
throttle grip and cable ............... 6-26
Checking and lubricating the
brake and shift pedals ............... 6-26
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
sidestand ................................... 6-27
Lubricating the swingarm pivots... 6-28
Checking the front fork ................. 6-28
Checking the steering ................... 6-29
Checking the wheel bearings ....... 6-29
Battery .......................................... 6-30
Replacing the fuses ...................... 6-31
Vehicle lights ................................. 6-32
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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.
EAU85050ON
All electrical circuits are supplied with
power and the vehicle lights are turned
on. The engine can be started. The key
cannot be removed.
TIP
To prevent battery discharge, do
not leave the key in the on position
without the engine running.
The headlight comes on automat-
ically when the engine is started.
The headlight will stay on until the
key is turned to “OFF”, 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.
1. Push.
2. Turn.
12
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Instrument and control functions
3-16
3
EAU13076
Fuel tank cap
To open the fuel tank cap
Open the fuel tank cap lock cover, in-
sert the key into the lock, and then turn
it 1/4 turn clockwise. The lock will be
released and the fuel tank cap can be
opened.
To close the fuel tank cap
With the key still inserted in the lock,
push down the fuel tank cap. Turn the
key 1/4 turn counterclockwise, remove
it, and then close the lock cover.
TIP
The fuel tank cap cannot be closed un-
less the key is in the lock. In addition,
the key cannot be removed if the cap is
not properly closed and locked.
WARNING
EWA11092
Make sure that the fuel tank cap is
properly closed after filling fuel.
Leaking fuel is a fire hazard.
EAU13213
Fuel
Make sure there is sufficient gasoline in
the tank.
WARNING
EWA10882
Gasoline and gasoline vapors are
extremely flammable. To avoid fires
and explosions and to reduce the
risk of injury when refueling, follow
these instructions.
1. Before refueling, turn off the en-
gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. Stop
filling when the fuel reaches the
bottom of the filler tube. Because
fuel expands when it heats up,
heat from the engine or the sun
can cause fuel to spill out of the
fuel tank.
3. Wipe up any spilled fuel immedi-
ately. NOTICE: Immediately
wipe off spilled fuel with a clean,1. Fuel tank cap lock cover
2. Unlock.
1
2
1. Fuel tank filler tube
2. Maximum fuel level
1
2
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Instrument and control functions
3-20
3
EAU14302
Helmet holder
The helmet holder is located under the
seat.
To secure a helmet to the helmet
holder
1. Open the seat. (See page 3-19.)
2. Attach the helmet to the helmet
holder, and then securely close
the seat. WARNING! Never ride
with a helmet attached to the
helmet holder, since the helmet
may hit objects, causing loss of
control and possibly an acci-
dent.
[EWA10162]
To release the helmet from the hel-
met holder
Open the seat, remove the helmet from
the helmet holder, and then close the
seat.
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.
1. Helmet holder
1
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Instrument and control functions
3-21
3
EAU83150
Ignition circuit cut-off system
This system prevents in-gear engine
starts unless the clutch lever is pulled
and the sidestand is up. Also, it will
stop the running engine should the
sidestand be lowered while the trans-
mission is in gear.
Periodically check the system via the
following procedure.
TIP
This check is most reliable if per-
formed with a warmed-up engine.
See pages 3-1 and 3-12 for switch
operation information.
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For your safety – pre-operation checks
4-2
4
Throttle grip• Make sure that operation is smooth.
• Check throttle grip free play.
• If necessary, have Yamaha dealer adjust throttle grip
free play and lubricate cable and grip housing.6-14,
6-26
Control cables• Make sure that operation is smooth.
• Lubricate if necessary.6-25
Drive chain• Check chain slack.
• Adjust if necessary.
• Check chain condition.
• Lubricate if necessary.6-23,
6-25
Wheels and tires•Check for damage.
• Check tire condition and tread depth.
• Check air pressure.
• Correct if necessary.6-15,
6-18
Brake and shift pedals• Make sure that operation is smooth.
• Lubricate pedal pivoting points if necessary.6-26
Brake and clutch le-
vers• Make sure that operation is smooth.
• Lubricate lever pivoting points if necessary.6-27
Sidestand• Make sure that operation is smooth.
• Lubricate pivot if necessary.6-27
Chassis fasteners• Make sure that all nuts, bolts and screws are properly
tightened.
• Tighten if necessary.—
Instruments, lights,
signals and switches• Check operation.
• Correct if necessary.—
Sidestand switch • Check operation of ignition circuit cut-off system.
• If system is not working correctly, have Yamaha dealer
check vehicle.3-20 ITEM CHECKS PAGE
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Operation and important riding points
5-2
51000 km (600 mi) and beyond
The vehicle can now be operated nor-
mally.
NOTICE
ECA10311
Keep the engine speed out of
the tachometer red zone.
If any engine trouble should oc-
cur during the engine break-in
period, immediately have a
Yamaha dealer check the vehi-
cle.
EAU86690
Starting the engine
The ignition circuit cut-off system will
enable starting when:
the transmission is in the neutral
position or
the transmission is in gear, the
sidestand is up, and the clutch le-
ver is pulled.
To start the engine
1. Turn the main switch on and set
the engine stop switch to the run
position.
2. Confirm the indicator and warning
light(s) come on for a few sec-
onds, and the go off. (See page
3-2.)
TIP
Do not start the engine if the en-
gine trouble warning light remains
on.
The ABS warning light should
come on and stay on until the ve-
hicle reaches a speed of 10 km/h
(6 mi/h).
NOTICE
ECA24110
If a warning or indicator light does
not work as described above, have a
Yamaha dealer check the vehicle.
3. Shift the transmission into the
neutral position.
4. Start the engine by pushing the
start switch.
5. Release the start switch when the
engine starts, or after 5 seconds.
Wait 10 seconds before pressing
the switch again to allow battery
voltage to restore.
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Periodic maintenance and adjustment
6-35
6
EAU25872
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from water
heaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or prop-
erty damage.
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