2020 YAMAHA MT-125 battery

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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Description
2-1
2
EAU63371
Left view
1234
65798
1. Fuel tank cap (page 3-16)
2. Battery (page 6-30)
3. Fuses (page 6-31)
4. Tool kit (page 6-2)
5. Sidestand (page 3-20)
6. Air filter check hose
7. Shift pedal (page 3-13)
8. Idle adjusting screw (page 6-13)
9. Coolant reservoir (page 6-11)
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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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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
6-30
6
EAU50583
Battery
The battery is located under the rider
seat. It is a VRLA (valve-regulated lead-
acid) battery. There is no need to check
the electrolyte or to add distilled water.
However, the battery lead connections
need to be checked, and tightened if
necessary.
WARNING
EWA10761
Electrolyte is poisonous and
dangerous since it contains sul-
furic acid, which causes severe
burns. Avoid any contact with
skin, eyes or clothing and al-
ways shield your eyes when
working near batteries. In case
of contact, administer the fol-
lowing FIRST AID.
EXTERNAL: Flush with plenty
of water.
INTERNAL: Drink large quan-
tities of water or milk and im-
mediately call a physician.
EYES: Flush with water for 15
minutes and seek prompt
medical attention.Batteries produce explosive hy-
drogen gas. Therefore, keep
sparks, flames, cigarettes, etc.,
away from the battery and pro-
vide sufficient ventilation when
charging it in an enclosed
space.
KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
NOTICE
ECA10621
Never attempt to remove the battery
cell seals, as this would permanently
damage the battery.
To charge the battery
Have your Yamaha dealer charge the
battery if it seems to have discharged.
Keep in mind that the battery tends to
discharge more quickly if the vehicle is
equipped with optional electrical ac-
cessories.
NOTICE
ECA16522
To charge a VRLA (Valve Regulated
Lead Acid) battery, a special (con-
stant-voltage) battery charger is re-
quired. Using a conventional battery
charger will damage the battery.
To store the battery
1. If the vehicle will not be used for
more than one month, remove the
battery, fully charge it, and then
place it in a cool, dry place.
NOTICE: When removing the
battery, be sure to turn the main
switch off, then disconnect the
negative lead before discon-
necting the positive lead.
[ECA16304]
1. Positive battery lead (red)
2. Battery
3. Negative battery lead (black)
1
2
3
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Periodic maintenance and adjustment
6-31
6 2. If the battery will be stored for
more than two months, check it at
least once a month and fully
charge it if necessary.
3. Fully charge the battery before in-
stallation. NOTICE: When install-
ing the battery, be sure to turn
the main switch off, then con-
nect the positive lead before
connecting the negative lead.
[ECA16842]
4. After installation, make sure that
the battery leads are properly con-
nected to the battery terminals.
NOTICE
ECA16531
Always keep the battery charged.
Storing a discharged battery can
cause permanent battery damage.
EAUB1116
Replacing the fuses
The fuse box is located under the seat.
(See page 3-19.)
If a fuse is blown, replace it as follows.
1. Turn the main switch off and turn
off the electrical circuit in ques-
tion.
2. Remove the blown fuse, and then
install a new fuse of the specified
amperage. WARNING! Do not
use a fuse of a higher amperage
rating than recommended to
avoid causing extensive dam-
age to the electrical system and
possibly a fire.
[EWA15132]
1. Fuse box
2. Spare fuse
3. Headlight fuse
4. ABS control unit fuse
5. Main fuse
6. ABS solenoid fuse
7. ABS motor fuse
8. Fuse tongs
157.5 2 1
5 7.5 1
5 3
0302
1
8
76543
2
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Periodic maintenance and adjustment
6-36
6
EAU86390
Troubleshooting chart
1. FuelThere is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine turns over
quickly.
The engine turns over
slowly.
Try starting the
engine.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug(s).
Check the battery
lead connections,
and charge the
battery if necessary.
2. BatteryThe battery is good.
The engine does not
start.
Check the ignition.
3. IgnitionWet
Dry
There is compression.
There is no
compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
Operate the electric
starter.
Try starting the
engine.
Check the fuel level
in the fuel tank.
4. Compression
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Motorcycle care and storage
7-5
78. Check and correct the tire air
pressure, and then lift the vehicle
so that all wheels are off the
ground. Otherwise, turn the
wheels a little once a month in or-
der to prevent the tires from be-
coming degraded in one spot.
9. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
10. Remove the battery and fully
charge it, or attach a maintenance
charger to keep the battery opti-
mally charged. NOTICE: Confirm
that the battery and its charger
are compatible. Do not charge a
VRLA battery with a convention-
al charger.
[ECA26330]
TIP
If the battery will be removed,
charge it once a month and store
it in a temperate location between
0-30 °C (32-90 °F).
See page 6-30 for more informa-
tion on charging and storing the
battery.
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