2015 YAMAHA MT-125 Owners Manual

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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PERIODIC MAINTENANCE AND ADJUSTMENT
6-29
6
EAU23284
Checking the steeringWorn 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. Place a stand under the engine to
raise the front wheel off the
ground. (See page 6-36 for more
information.) WARNING! To
avoid injury, securely 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 bearingsThe 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.
ZAUM1213
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-30
6
EAU23315
BatteryA poorly maintained battery will cor-
rode and discharge quickly. The elec-
trolyte level, battery lead connections
and breather hose routing should be
checked before each ride and at the in-
tervals specified in the periodic main-
tenance and lubrication chart.
WARNING
EWA10771
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.
Take care not to spill electrolyte
on the drive chain, as this may
weaken it, shorten chain life and
possibly result in an accident.
KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
To check the electrolyte level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.TIPMake sure that the vehicle is posi-
tioned straight up when checking the
electrolyte level.2. Check the electrolyte level in the
battery.
TIPThe electrolyte should be between the
minimum and maximum level marks.3. If the electrolyte is at or below the
minimum level mark, add distilled
water to raise it to the maximum
level mark. NOTICE: Use only
distilled water, as tap water
contains minerals that are
harmful to the battery.
[ECA10612]
4. Check and, if necessary, tighten
the battery lead connections and
correct the breather hose routing.1. Maximum level mark
2. Minimum level mark1
2
+
UPPER
LOWER
ZAUM0106
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