2020 YAMAHA MT-125 brake

Periodic maintenance and adjustment
6-16
6
WARNING
EWA10512
Never overload your vehicle. Opera-
tion of an overloaded vehicle could
cause an accident.
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail
or glass fragments in it, or if the side-
wall is cracked, have a Yamaha dealer
replace the tire immediately.
TIP
The tire tread depth limits may differ
from country to country. Always com-
ply with the local regulations.
WARNING
EWA10472
Have a Yamaha dealer replace
excessively worn tires. Besides
being illegal, operating the vehi-
cle with excessively worn tires
decreases riding stability and
can lead to loss of control.
The replacement of all wheel
and brake-related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-
edge and experience to do so.
Ride at moderate speeds after
changing a tire since the tire
surface must first be “broken
in” for it to develop its optimal
characteristics.
Tire information
Cold tire air pressure:
1 person:
Front:
200 kPa (2.00 kgf/cm², 29 psi)
Rear:
220 kPa (2.20 kgf/cm², 32 psi)
2 persons:
Front:
200 kPa (2.00 kgf/cm², 29 psi)
Rear:
220 kPa (2.20 kgf/cm², 32 psi)
Maximum load:
Vehicle:
180 kg (397 lb)
The vehicle’s maximum load is the
combined weight of the rider, pas-
senger, cargo, and any accessories.
1. Tire sidewall
2. Tire tread depth
Minimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
1. Tire air valve
2. Tire air valve core
3. Tire air valve cap with seal
123
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Periodic maintenance and adjustment
6-19
6 5. Loosen the locknut at the crank-
case.
6. To increase the clutch lever free
play, turn the clutch lever free play
adjusting nut in direction (a). To
decrease the clutch lever free
play, turn the adjusting nut in di-
rection (b).
7. Tighten the locknut at the crank-
case.
8. Tighten the locknut at the clutch
lever and then slide the rubber
cover to its original position.
EAUT1223
Checking the front brake lever
free play
Measure the front brake lever free play
as shown.
Periodically check the brake lever free
play and, if necessary, have a Yamaha
dealer check the brake system.
WARNING
EWA10642
An incorrect brake lever free play in-
dicates a hazardous condition in the
brake system. Do not operate the
vehicle until the brake system has
been checked or repaired by a
Yamaha dealer.
1. Locknut
2. Clutch lever free play adjusting nut (crank-
case)
1 2 (a)
(b)
1. Brake lever free play
Front brake lever free play:
2.0–5.0 mm (0.08–0.20 in)
1
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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
6-21
6
EAU22393
Checking the front and rear
brake pads
The front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22421Front brake pads
Each front brake pad is provided with a
wear indicator groove, which allows
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator groove. If a brake
pad has worn to the point that the wear
indicator groove has almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU36721Rear brake pads
Each rear brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear
indicator grooves have almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
1. Wear indicator groove
ZAUM1466
1
1. Wear indicator groove
ZAUM1601
1
1
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Periodic maintenance and adjustment
6-22
6
EAU40262
Checking the brake fluid level
Before riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the top
of the reservoir level. Replenish the
brake fluid if necessary.
Front brake
Rear brake
WARNING
EWA16011
Improper maintenance can result in
loss of braking ability. Observe
these precautions:
Insufficient brake fluid may al-
low air to enter the brake sys-
tem, reducing braking
performance.Clean the filler cap before re-
moving. Use only DOT 4 brake
fluid from a sealed container.
Use only the specified brake flu-
id; otherwise, the rubber seals
may deteriorate, causing leak-
age.
Refill with the same type of
brake fluid. Adding a brake fluid
other than DOT 4 may result in a
harmful chemical reaction.
Be careful that water or dust
does not enter the brake fluid
reservoir when refilling. Water
will significantly lower the boil-
ing point of the fluid and may re-
sult in vapor lock, an
d dirt may
clog the ABS hydraulic unit
valves.
NOTICE
ECA17641
Brake fluid may damage painted
surfaces or plastic parts. Always
clean up spilled fluid immediately.
As the brake pads wear, it is normal for
the brake fluid level to gradually go
down. A low brake fluid level may indi-
cate worn brake pads and/or brake
system leakage; therefore, be sure to
check the brake pads for wear and the
brake system for leakage. If the brake
fluid level goes down suddenly, have a
Yamaha dealer check the cause before
further riding.
1. Minimum level mark
1. Minimum level mark
Specified brake fluid:
DOT 4
1
ZAUM1057
1
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Periodic maintenance and adjustment
6-23
6
EAU22734
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid every 2 years. In addition,
have the seals of the master cylinders
and brake calipers, as well as the brake
hoses replaced at the intervals listed
below or sooner if they are damaged or
leaking.
Brake seals: every 2 years
Brake hoses: every 4 years
EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU74253To 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 as
shown.
4. If the drive chain slack is incorrect,
adjust it as follows. NOTICE: Im-
proper drive chain slack will
overload the engine as well as
other vital parts of the motorcy-
cle and can lead to chain slip-
page or breakage. To prevent
this from occurring, keep the
drive chain slack within the
specified limits.
[ECA10572]
1. Drive chain slack
Drive chain slack:
30.0–40.0 mm (1.18–1.57 in)
ZAUM1604
1
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Periodic maintenance and adjustment
6-26
6
EAU23115
Checking and lubricating the
throttle grip and cable
The operation of the throttle grip
should be checked before each ride. In
addition, the cable should be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
chart.
The throttle cable is equipped with a
rubber cover. Make sure that the cover
is securely installed. Even though the
cover is installed correctly, it does not
completely protect the cable from wa-
ter entry. Therefore, use care not to
pour water directly onto the cover or
cable when washing the vehicle. If the
cable or cover becomes dirty, wipe
clean with a moist cloth.
EAU44276
Checking and lubricating the
brake and shift pedals
The operation of the brake and shift
pedals should be checked before each
ride, and the pedal pivots should be lu-
bricated if necessary.
Brake pedal
Shift pedal
Recommended lubricant:
Lithium-soap-based grease
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Periodic maintenance and adjustment
6-27
6
EAU23144
Checking and lubricating the
brake and clutch levers
The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be lu-
bricated if necessary.
Brake lever
Clutch lever
EAU23203
Checking and lubricating the
sidestand
The operation of the sidestand should
be checked before each ride, and the
sidestand pivot and metal-to-metal
contact surfaces should be lubricated
if necessary.
WARNING
EWA10732
If the sidestand does not move up
and down smoothly, have a Yamaha
dealer check or repair it. Otherwise,
the sidestand could contact the
ground and distract the operator, re-
sulting in a possible loss of control.
Recommended lubricants:
Brake lever:
Silicone grease
Clutch lever:
Lithium-soap-based grease
Recommended lubricant:
Lithium-soap-based grease
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