YAMAHA MT-125 2015 Repair Manual

PERIODIC MAINTENANCE AND ADJUSTMENT
6-19
6
EAU21963
Cast wheelsTo maximize the performance, durabil-
ity, and safe operation of your vehicle,
note the following points regarding the
specified wheels.
The wheel rims should be
checked for cracks, bends, warp-
age or other damage before each
ride. If any damage is found, have
a Yamaha dealer replace the
wheel. Do not attempt even the
smallest repair to the wheel. A de-
formed or cracked wheel must be
replaced.
The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.
EAU22045
Adjusting the clutch lever free
playThe clutch lever free play should mea-
sure 10.0–15.0 mm (0.39–0.59 in) as
shown. Periodically check the clutch
lever free play and, if necessary, adjust
it as follows.
1. Slide the rubber cover back at the
clutch lever.
2. Loosen the locknut.
3. To increase the clutch lever free
play, turn the clutch lever free play
adjusting bolt in direction (a). To
decrease the clutch lever free
play, turn the adjusting bolt in di-
rection (b).
TIPIf the specified clutch lever free play
could be obtained as described above,
skip steps 4–7.4. Fully turn the adjusting bolt at the
clutch lever in direction (a) to loos-
en the clutch cable.
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).
1. Clutch lever free play adjusting bolt
2. Clutch lever free play
1. Locknut
2. Clutch lever free play adjusting nut (crank-
case)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-20
67. 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.
EAUT1222
Checking the front brake lever
free playThe brake lever free play should mea-
sure 2.0–5.0 mm (0.08–0.20 in) as
shown. Periodically check the brake le-
ver free play and, if necessary, have a
Yamaha dealer check the brake sys-
tem.
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.
EAUM1354
Adjusting the brake pedal free
playThe brake pedal free play should mea-
sure 3.5–4.5 mm (0.14–0.18 in) 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.
1. Brake lever free playZAUM1179
INFOINFO
1. Brake pedal free play
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-21
6
EAUM3541
Brake light switchesFor ABS models
The brake light, which is activated by
the brake pedal and brake lever,
should come on just before braking
takes effect. If necessary, adjust the
rear brake light switch as follows, but
the front brake light switch should be
adjusted by a Yamaha dealer.
Turn the rear brake light switch adjust-
ing nut while holding the rear brake
light switch in place. To make the
brake light come on earlier, turn the ad-justing nut in direction (a). To make the
brake light come on later, turn the ad-
justing nut in direction (b).
For non-ABS models
The brake light, which is activated by
the brake pedal and brake lever,
should come on just before braking
takes effect. If necessary, have a
Yamaha dealer check the brake light
switches.
EAU22393
Checking the front and rear
brake padsThe front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22421
Front 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
1. Rear brake light switch
2. Rear brake light switch adjusting nutZAUM1230
2
(a)(b)
1. Wear indicator grooveZAUM1180
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-22
6indicator groove has almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU22501
Rear brake pads
Check each rear brake pad for damage
and measure the lining thickness. If a
brake pad is damaged or if the lining
thickness is less than 1.5 mm (0.06 in),
have a Yamaha dealer replace the
brake pads as a set.
EAU40262
Checking the brake fluid levelBefore 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 brakeRear 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.
1. Lining thickness
1. Minimum level markZAUM1209
I
NFOI
NFO
1. Minimum level markSpecified brake fluid:
DOT 4
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-23
6 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, and 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 brakefluid level goes down suddenly, have a
Yamaha dealer check the cause before
further riding.
EAU22733
Changing the brake fluidHave a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the oil seals
of the master cylinders and calipers as
well as the brake hoses replaced at the
intervals listed below or whenever they
are damaged or leaking.
Oil seals: Replace every two
years.
Brake hoses: Replace every four
years.
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-24
6
EAU22762
Drive chain slackThe drive chain slack should be
checked before each ride and adjusted
if necessary.
EAUM3550
To check the drive chain slack
1. Place the motorcycle on the side-
stand.TIPWhen 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 at
the arrow mark on the swingarm
as shown in the illustration.4. If the drive chain slack is incorrect,
adjust it as follows.
EAU34318
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.
1. Loosen the axle nut and the lock-
nut on each side of the swingarm.2. To tighten the drive chain, turn the
drive chain slack adjusting bolt on
each side of the swingarm in di-
rection (a). To loosen the drive
chain, turn the adjusting bolt on
each side of the swingarm in di-
rection (b), and then push the rear
wheel forward. NOTICE: Improp-
er drive chain slack will over-
load the engine as well as other
vital parts of the motorcycle and
can lead to chain slippage or
breakage. To prevent this from
Drive chain slack:
35.0–45.0 mm (1.38–1.77 in)
1. Drive chain slackZAUM1233
1. Axle nut
2. Drive chain slack adjusting bolt
3. Locknut
4. Alignment marksZAUM1183
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-25
6 occurring, keep the drive chain
slack within the specified limits.
[ECA10572]
TIPUsing the alignment marks on each
side of the swingarm, make sure that
both drive chain pullers are in the same
position for proper wheel alignment.3. Tighten the axle nut, then the lock-
nuts to their specified torques.
4. Make sure that the drive chain
pullers are in the same position,
the drive chain slack is correct,
and the drive chain moves
smoothly.
EAU23026
Cleaning and lubricating the
drive chainThe drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.NOTICE
ECA10584
The drive chain must be lubricated
after washing the motorcycle, riding
in the rain or riding in wet areas.1. Clean the drive chain with kero-
sene and a small soft brush.
NOTICE: To prevent damaging
the O-rings, do not clean the
drive chain with steam cleaners,
high-pressure washers or inap-
propriate solvents.
[ECA11122]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant. NOTICE: Do not use
engine oil or any other lubri-
cants for the drive chain, as theymay contain substances that
could damage the O-rings.
[ECA11112]
Tightening torques:
Axle nut:
85 Nm (8.5 m·kgf, 61 ft·lbf)
Locknut:
16 Nm (1.6 m·kgf, 12 ft·lbf)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-26
6
EAU23098
Checking and lubricating the
cablesThe operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubri-
cated if necessary. If a cable is
damaged or does not move smoothly,
have a Yamaha dealer check or re-
place it. WARNING! Damage to the
outer housing of cables may result
in internal rusting and cause inter-
ference with cable movement. Re-
place damaged cables as soon as
possible to prevent unsafe condi-
tions.
[EWA10712]EAU23115
Checking and lubricating the
throttle grip and cableThe 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.
EAU23144
Checking and lubricating the
brake and clutch leversThe 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
Recommended lubricant:
Yamaha cable lubricant or other
suitable cable lubricant
ZAUM1184
I
NFOI
NFO
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-27
6
EAU23185
Checking and lubricating the
brake pedalThe operation of the brake pedal
should be checked before each ride,
and the pedal pivot should be lubricat-
ed if necessary.
EAU23203
Checking and lubricating the
sidestandThe 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 greaseZAUM1234
Recommended lubricant:
Lithium-soap-based greaseZAUM1211
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-28
6
EAUM1653
Lubricating the swingarm piv-
otsThe swingarm pivots must be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU23273
Checking the front forkThe condition and operation of the
front fork must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
To check the condition
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion. WARNING! To avoid injury,
securely support the vehicle so
there is no danger of it falling
over.
[EWA10752]
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
NOTICE
ECA10591
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it.
Recommended lubricant:
Lithium-soap-based grease
ZAUM1212
YA M A H A
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