2020 YAMAHA MT-03 Owners Manual

Periodic maintenance and adjustment
6-21
6
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.EAU22583
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 res-
ervoir in an upright position. Replenish
the brake fluid if necessary.
NOTICE
ECA17641
Brake fluid may damage painted
surfaces or plastic parts. Always
clean up spilled fluid immediately.
Front brake
Rear brake
As the brake pads wear, it is normal for
the brake fluid level to gradually go
down.
1. Brake pad wear indicator groove
1
1Specified brake fluid:
DOT 4
1. Minimum level mark
1. Minimum level mark
1
1
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Periodic maintenance and adjustment
6-22
6A low brake fluid level may indi-
cate worn brake pads 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 rid-
ing.
WARNING
EWA15991
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 does not
enter the brake fluid reservoir
when refilling. Water will signifi-
cantly lower the boiling point of
the fluid and may result in vapor
lock.
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
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Periodic maintenance and adjustment
6-23
6
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]EAU62983
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.
1. Remove the drive chain puller cap,
and then loosen the axle nut and
the locknut on each side of the
swingarm.
2. To tighten the drive chain, turn the
drive chain slack adjusting nut on
each side of the swingarm in di-
rection (a). To loosen the drive
chain, turn the adjusting nut on
each side of the swingarm in di-
rection (b), and then push the rear
wheel forward.
1. Drive chain slack
Drive chain slack:
35.0–45.0 mm (1.38–1.77 in)
1
1. Axle nut
2. Locknut
3. Drive chain puller cap
1. Drive chain slack adjusting nut
2
3
1
1(a)
(b)
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Periodic maintenance and adjustment
6-24
6
TIP
Using 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.
5. Install the drive chain puller caps.
EAU23026
Cleaning and lubricating the
drive chain
The 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 they
may contain substances that
could damage the O-rings.
[ECA11112]
1. Alignment marks
2. Drive chain puller
Tightening torques:
Axle nut:
57 N·m (5.7 kgf·m, 42 lb·ft)
Locknut:
16 N·m (1.6 kgf·m, 12 lb·ft)
1 2
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Periodic maintenance and adjustment
6-25
6
EAU23098
Checking and lubricating the
cables
The 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]EAU49921
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.
Recommended lubricant:
Yamaha cable lubricant or other
suitable cable lubricant
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Periodic maintenance and adjustment
6-26
6
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
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
Recommended lubricant:
Lithium-soap-based greaseRecommended lubricants:
Brake lever:
Silicone grease
Clutch lever:
Lithium-soap-based grease
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Periodic maintenance and adjustment
6-27
6
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.
EAUM1653
Lubricating the swingarm piv-
ots
The swingarm pivots must be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
and lubrication chart.
Recommended lubricant:
Lithium-soap-based grease
Recommended lubricant:
Lithium-soap-based grease
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Periodic maintenance and adjustment
6-28
6
EAU23273
Checking the front fork
The 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.
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.
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