2017 YAMAHA MT-125 light

Operation and important riding points
5-4
5
EAU16811
Tips for reducing fuel con-
sumption
Fuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
Shift up swiftly, and avoid high en-
gine speeds during acceleration.
Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the en-
gine.
Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at traf-
fic lights or at railroad crossings).
EAU16831
Engine break-in
There is never a more important period
in the life of your engine than the period
between 0 and 1000 km (600 mi). For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1000 km (600 mi). The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that
might result in engine overheating
must be avoided.
EAU16983
0–500 km (0–300 mi)
Avoid prolonged operation above 6000
r/min.
After every hour of operation, stop the
engine, and then let it cool for five to
ten minutes.
Vary the engine speed from time to
time. Do not operate the engine at one
set throttle position.
500–1000 km (300–600 mi)
Avoid prolonged operation above 8000
r/min.
Rev the engine freely through the
gears, but do not use full throttle at any
time. NOTICE: After 1000 km (600 mi)
of operation, the engine oil must be
changed, the oil filter cartridge or el-
ement replaced, and the oil strainer
cleaned.
[ECA10322]
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Periodic maintenance and adjustment
6-6
6
EAU72740
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 change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
25 Engine oil• Change (warm engine before
draining).At the initial interval and when
the oil change indicator flashes
or comes on
• Check oil level and vehicle for oil
leakage.Every 3000 km (1800 mi)
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
6-8
6
EAU19607
Checking the spark plug
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic main-
tenance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light
tan (the ideal color when the vehi-
cle is ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifi-
cation.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
NGK/CR9E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
1
ZAUM0037
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Periodic maintenance and adjustment
6-9
6 To install the spark plug
1. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
2. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
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.
3. Install the spark plug cap.
EAUM3491
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.
Tightening torque:
Spark plug:
12.5 N·m (1.25 kgf·m, 9.04 lb·ft)
1. Engine oil filler cap
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Periodic maintenance and adjustment
6-12
613. Turn the engine off, and then
check the oil level and correct it if
necessary.
14. Reset the oil change indicator.
(See page 3-10.)
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.
EAUM1726To check the coolant level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
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.
2. Check the coolant level in the
coolant reservoir.
TIP
The coolant should be between the
minimum and maximum level marks.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
ZAUM1207
FULL
LOW2
3
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Periodic maintenance and adjustment
6-21
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.
EAU36504
Brake light switches
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 adjust the brake light
switches.
1. Brake pedal free play
Brake pedal free play:
3.5–4.5 mm (0.14–0.18 in)
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Periodic maintenance and adjustment
6-33
6
3. Turn the key to “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.
EAUM3501
Replacing the headlight bulb
This model is equipped with a halogen
bulb headlight. If the headlight bulb
burns out, replace it as follows.
NOTICE
ECA10651
Take care not to damage the follow-
ing parts:
Headlight bulb
Do not touch the glass part of
the headlight bulb to keep it free
from oil, otherwise the transpar-
ency of the glass, the luminosity
of the bulb, and the bulb life will
be adversely affected. Thor-
oughly clean off any dirt and fin-
gerprints on the headlight bulb
using a cloth moistened with al-
cohol or thinner.
Headlight lens
Do not affix any type of tinted
film or stickers to the headlight
lens.
Do not use a headlight bulb of a
wattage higher than specified.
1. Remove the headlight unit by re-
moving the bolts on each side.
1. Headlight fuse
2. Signaling system fuse
3. Ignition fuse
4. Radiator fan motor fuse
5. Main fuse
6. ABS control unit fuse
7. Spare fuse
8. Backup fuse
9. ABS solenoid fuse
10.ABS motor fuse
Specified fuses:
Main fuse:
20.0 A
Ignition fuse:
7.5 A
Signaling system fuse:
7.5 A
Headlight fuse:
15.0 A
Radiator fan motor fuse:
5.0 A
ABS control unit fuse:
10.0 A
ABS motor fuse:
30.0 A
ABS solenoid fuse:
20.0 A
Backup fuse:
10.0 A
ZAUM1231
10
303020
7
8
91010
157.5
207.5 7.515
5 20
5
7
12
3
45
6
1. Do not touch the glass part of the bulb.
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Periodic maintenance and adjustment
6-34
62. Disconnect the headlight coupler,
and then remove the headlight
bulb cover.
3. Remove the headlight bulb holder
by turning it counterclockwise,
and then remove the burnt-out
bulb.4. Place a new headlight bulb into
position, and then secure it with
the bulb holder.
5. Install the headlight bulb cover,
and then connect the coupler.
6. Install the headlight unit as shown,
and then install the bolt on each
side.
TIP
Check the wire routing when headlight
unit is installed in order to avoid wire
pinching and coupler disconnection.
7. Have a Yamaha dealer adjust the
headlight beam if necessary.
1. Bolt
1. Headlight bulb cover
2. Headlight coupler
1. Headlight bulb
2. Headlight bulb holder
ZAUM1220
1
ZAUM1221
21
ZAUM1222
2
1
ZAUM1224
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