light YAMAHA MT-125 2020 Owner's Manual

Periodic maintenance and adjustment
6-6
6
EAU72750
TIP
The air filter needs more frequent service if you are riding in unusually wet or
dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cyl-
inders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
26Engine oil filter el-
ement• Replace.√√√√√
27*Cooling system• Check coolant level and vehicle
for coolant leakage.√√√√√
• Change. Every 3 years
28*Front and rear
brake switches• Check operation.√√√√√√
29*Moving parts and
cables• Lubricate.√√√√√
30*Throttle grip hous-
ing and cable• Check operation and free play.
• Adjust the throttle cable free
play if necessary.
• Lubricate the throttle grip hous-
ing and cable.√√√√√
31*Lights, signals and
switches• Check operation.
• Adjust headlight beam.√√√√√√ NO. ITEM
X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READING
ANNUAL CHECK
16121824
0.6 3.5 7 10.5 14
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Periodic maintenance and adjustment
6-7
6
EAU18782
Removing and installing cowl-
ings
The cowlings shown need to be re-
moved to perform some of the mainte-
nance jobs described in this chapter.
Refer to this section each time a cowl-
ing needs to be removed and installed.
EAU46742Cowling A
To remove the cowling
Remove the bolts, and then take the
cowling off.
To install the cowling
Place the cowling in the original posi-
tion, and then install the bolts.
EAU19623
Checking the spark plug
The spark plug is an important engine
component, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode,
it should be removed and checked in
accordance with the periodic mainte-
nance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally). If the spark plug shows a
distinctly different color, the engine
could be operating improperly. Do not
attempt to diagnose such problems
yourself. Instead, have a Yamaha deal-
er check the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon or
other deposits, it should be replaced.
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
1. Cowling A
1. Bolt
ZAUM17381
1
Specified spark plug:
NGK/MR8E9
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Periodic maintenance and adjustment
6-8
6Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the spark
plug threads.
TIP
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4…
1/2 turn past finger tight. However, the
spark plug should be tightened to the
specified torque as soon as possible.
EAUM2584
Engine oil and oil filter ele-
ment
The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter ele-
ment replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart.
To check the engine oil level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion. A slight tilt to the side can
result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.
NOTICE: Do not operate the ve-
hicle until you know that the en-
gine oil level is sufficient.
[ECA10012]
TIP
The engine oil should be between the
minimum and maximum level marks.
1. Spark plug gap
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
Tightening torque:
Spark plug:
12.5 N·m (1.25 kgf·m, 9.22 lb·ft)
1
ZAUM0037
1. Engine oil filler cap
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Periodic maintenance and adjustment
6-11
6
EAU85450
Why Yamalube
YAMALUBE oil is a Genuine YAMAHA
Part born of the engineers’ passion
and belief that engine oil is an impor-
tant liquid engine component. We form
teams of specialists in the fields of me-
chanical engineering, chemistry, elec-
tronics and track testing, and have
them develop the engine together with
the oil it will use. Yamalube oils take full
advantage of the base oil’s qualities
and blend in the ideal balance of addi-
tives to make sure the final oil clears
our performance standards. Thus,
Yamalube mineral, semisynthetic and
synthetic oils have their own distinct
characters and value. Yamaha’s expe-
rience gained over many years of re-
search and development into oil since
the 1960’s helps make Yamalube the
best choice for your Yamaha engine.
EAU20071
Coolant
The coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUE4091To check the coolant level
1. Place the vehicle on a level sur-
face.
2. Remove cowling A. (See page
6-7.)
3. Hold the vehicle in an upright po-
sition.
TIP
The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.
4. Check the coolant level in the
coolant reservoir.
TIP
The coolant should be between the
minimum and maximum level marks.
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Periodic maintenance and adjustment
6-20
6
EAUM1355
Adjusting the brake pedal free
play
Measure the brake pedal free play as
shown.
Periodically check the brake pedal free
play and, if necessary, have a Yamaha
dealer adjust it.
WARNING
EWAM1031
An incorrect brake pedal free play
indicates a hazardous condition in
the brake system. Do not operate
the motorcycle until the brake sys-
tem has been checked or repaired
by a Yamaha dealer.
EAU36505
Brake light switches
The brake light should come on just
before braking takes effect. The brake
light is activated by switches connect-
ed to the brake lever and brake pedal.
Since the brake light switches are
components of the anti-lock brake sys-
tem, they should only be serviced by a
Yamaha dealer.
1. Brake pedal free play
Brake pedal free play:
7.0–13.0 mm (0.28–0.51 in)
1
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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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