2020 YAMAHA MT-125 Owners Manual

Periodic maintenance and adjustment
6-29
6
EAU23285
Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Raise the front wheel off the
ground. (See page 6-34.)
WARNING! To avoid injury, se-
curely support the vehicle so
there is no danger of it falling
over.
[EWA10752]
2. Hold the lower ends of the front
fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steer-
ing.
EAU23292
Checking the wheel bearings
The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
ZAUM1744
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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
6-32
63. Turn the main switch on and turn
on the electrical circuit in question
to check if the device operates.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
EAUN2261
Vehicle lights
This model is equipped with LED lights
for headlights, auxiliary lights and
brake/tail light. If a light does not come
on, check the fuse and then have a
Yamaha dealer check the vehicle.
NOTICE
ECA16581
Do not affix any type of tinted film or
stickers to the headlight lens.
Specified fuses:
Main fuse:
15.0 A
ABS motor fuse:
30.0 A
ABS solenoid fuse:
15.0 A
ABS control unit fuse:
2.0 A
Headlight fuse:
7.5 A
1. Auxiliary light
2. Headlight
21
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Periodic maintenance and adjustment
6-33
6
EAU24182
Tail/brake light
This model is equipped with an LED-
type tail/brake light.
If the tail/brake light does not come on,
have a Yamaha dealer check it.
EAU62590
Replacing a turn signal light
bulb
1. 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 overtighten the screw, oth-
erwise the lens may break.
[ECA11192]
1. Screw
1. Turn signal light bulb
1
ZAUM1609
1
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Periodic maintenance and adjustment
6-34
6
EAUM3510
Replacing the license plate
light bulb
1. 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.
EAU67131
Supporting the motorcycle
Since this model is not equipped with a
centerstand, use maintenance stands
when removing the front or rear wheel
or when performing other maintenance
that requires the motorcycle to stand
up right.
Check that the motorcycle is in a stable
and level position before starting any
maintenance.
1. License plate light bulb socket
2. License plate light unit
3. Screw
ZAUM1621
2
3
1. Maintenance stand (example)
1
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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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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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