2015 YAMAHA MAJESTY S 125 engine

PERIODIC MAINTENANCE AND ADJUSTMENT
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erosion and excessive carbon or
other deposits, and replace it if
necessary.
To install the spark plug 1. Measure the spark plug gap with a wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
2. Clean the surface of the spark plug gasket and its mating surface, and
then wipe off any grime from the spark plug threads.
3. Install the spark plug with the spark plug wrench, and then tight-
en it to the specified torque.
TIPIf 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 speci-fied torque as soon as possible.
4. Install the spark plug cap.
5. Install the panel.
EAUT4160
Engine oil and oil strainerThe engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil strainer
cleaned at the intervals specified in the
periodic maintenance and lubrication
chart.
To check the engine oil level1. Place the scooter on the center- stand. 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.
Specified spark plug:NGK / CPR8EA1. Spark plug gapSpark plug gap:0.8–0.9 mm (0.031–0.035 in)
1
ZAUE0032
Tightening torque:Spark plug:12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
1. Oil filler cap
2. Maximum level mark
3. Minimum level mark
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PERIODIC MAINTENANCE AND ADJUSTMENT
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93. 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.
TIPThe engine oil should be between theminimum and maximum level marks.
4. If the engine oil is below the mini- mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil and clean
the oil strainer 1. Start the engine, warm it up for several minutes, and then turn it
off.
2. Place an oil pan under the engine to collect the used oil.
3. Remove the engine oil filler cap and the engine oil drain bolts A
and B to drain the oil from the
crankcase. NOTICE: When re- moving the engine oil drain bolt
B, the O-ring, compression
spring, and oil strainer will fall
out. Take care not to lose these
parts.
[ECAT1022]
4. Clean the oil strainer with solvent,
and then check it for damage and
replace it if necessary.
5. Check the O-ring for damage and replace it if necessary.
6. Install the oil strainer, compression spring, O-ring and engine oil drain
bolt B.TIPMake sure that the O-ring is properlyseated.
7. Install engine oil drain bolt A, and then tighten both drain bolts to
1. Engine oil drain bolt A
1
1. Engine oil drain bolt B
2. O-ring
3. Compression spring
4. Oil strainer
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PERIODIC MAINTENANCE AND ADJUSTMENT
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their specified torques.
8. Refill with the specified amount of the recommended engine oil, and
then install and tighten the oil filler
cap.
NOTICE
ECA11671

Do not use oils with a diesel
specification of “CD” or oils of a
higher quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.

Be sure no foreign material en-ters the crankcase.
9. Start the engine, and then let it idle for several minutes while checking it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.
10. Turn the engine off, and then check the oil level and correct it if
necessary.
11. Reset the oil change indicator and oil change tripmeter. (See
page 3-4.)
EAU20067
Final transmission oilThe final transmission case must be
checked for oil leakage before each
ride. If any leakage is found, have a
Yamaha dealer check and repair the
scooter. In addition, the final transmis-
sion oil must be changed as follows at
the intervals specified in the periodic
maintenance and lubrication chart.1. Start the engine, warm up the final transmission oil by riding the
scooter for several minutes, and
then stop the engine.
2. Place the scooter on the center- stand.
3. Place an oil pan under the final transmission case to collect the
used oil.
4. Remove the final transmission oil filler cap and its O-ring from the fi-
nal transmission case.
Tightening torque:Engine oil drain bolt A:20 Nm (2.0 m·kgf, 14 ft·lbf)
Engine oil drain bolt B: 32 Nm (3.2 m·kgf, 23.1 ft·lbf)
Recommended engine oil: See page 8-1.
Oil change quantity: 0.95 L (1.00 US qt, 0.84 Imp.qt)



PERIODIC MAINTENANCE AND ADJUSTMENT
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95. Remove the final transmission oil
drain bolt and its gasket to drain
the oil from the final transmission
case.
6. Install the final transmission oil drain bolt and its new gasket, and then tighten the bolt to the speci-
fied torque.
7. Refill with the specified amount of the recommended final transmis-
sion oil. WARNING! Make sure
that no foreign material enters
the final transmission case.
Make sure that no oil gets on the
tire or wheel.
[EWA11312]
8. Install the final transmission oil fill- er cap and its new O-ring, and then
tighten the oil filler cap.
9. Check the final transmission case for oil leakage. If oil is leaking,
check for the cause.
EAU20071
CoolantThe 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.
EAUT1525
To check the coolant level
The coolant level should be checked as
follows before each ride. In addition,
the coolant must be changed at the in-
tervals specified in the periodic mainte-
nance and lubrication chart.1. Place the vehicle on the center- stand.TIP
The coolant level must be checked
on a cold engine since the level
varies with engine temperature.

Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to theside can result in a false reading.
2. Check the coolant level in the cool- ant reservoir.
1. Final transmission oil filler cap
1. Final transmission oil drain bolt
1
1
Tightening torque:Final transmission oil drain bolt: 20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended final transmission
oil: See page 8-1.
Oil quantity:
0.20 L (0.21 US qt, 0.18 Imp.qt)



PERIODIC MAINTENANCE AND ADJUSTMENT
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TIPThe coolant should be between theminimum and maximum level marks.3. If the coolant is at or below the minimum level mark, remove pan-
el C and the reservoir cap. (See
page 6-8.) WARNING! Remove
only the coolant reservoir cap.
Never attempt to remove the ra-
diator cap when the engine is
hot.
[EWA15162]
4. Add coolant or distilled water to raise the coolant to the maximum
level mark, and install the coolant
reservoir cap and the panel. NO-
TICE: If coolant is not available,
use distilled water or soft tap
water instead. Do not use hard
water or salt water since it is
harmful to the engine. If water
has been used instead of cool-
ant, replace it with coolant as
soon as possible, otherwise the
cooling system will not be pro-
tected against frost and corro-
sion. If water has been added to
the coolant, have a Yamaha
dealer check the antifreeze con- tent of the coolant as soon as
possible, otherwise the effec-
tiveness of the coolant will be
reduced.
[ECA10473]
EAU33032
Changing the coolant
The coolant must be changed at the in-
tervals specified in the periodic mainte-
nance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove
the radiator cap when the engine is
hot.
[EWA10382]
1. Maximum level mark
2. Minimum level mark
12
1. Coolant reservoir cap
1
Coolant reservoir capacity:0.25 L (0.26 US qt, 0.22 Imp.qt)



PERIODIC MAINTENANCE AND ADJUSTMENT
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EAUT4180
Air filter and V-belt case air
filter elementsThe air filter and V-belt case air filter el-
ements should be cleaned or replaced
at the intervals specified in the periodic
maintenance and lubrication chart.
Check both filter elements more fre-
quently if you are riding in unusually
wet or dusty areas. The air filter check
hose must be frequently checked and
cleaned if necessary.
Replacing the air filter element
1. Place the scooter on the center- stand.
2. Remove the screw cover and then remove the air filter case cover by
removing the screws. 3. Pull the air filter element out.
4. Insert a new air filter element into
the air filter case. NOTICE: Make
sure that the air filter element is properly seated in the air filter
case. The engine should never
be operated without the air filter
element installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively worn.
[ECA10482]
5. Install the air filter case cover by in-
stalling the screws and the screw
cover.
Cleaning the air filter check hose 1. Check the hose on the rear side of the air filter case for accumulated
dirt or water.
2. If dirt or water is visible, remove the hose, clean it, and then install
it.
Cleaning the V-belt case air filter el-
ement 1. Remove the V-belt air filter case cover by removing the bolts.
1. Screw cover
2. Air filter case cover
3. Air filter check hose
1. Air filter element
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PERIODIC MAINTENANCE AND ADJUSTMENT
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2. Pull the air filter element out, and
then clean it with compressed air.
NOTICE: To avoid damaging the
air filter element, handle it gen-
tly and carefully, and do not
twist it.
[ECA10522]
3. Insert the element into the air filter case.
4. Install the V-belt air filter case cov- er by installing the bolts.
EAU44735
Checking the engine idling
speedCheck the engine idling speed and, if
necessary, have it corrected by a
Yamaha dealer.
1. Bolt
2. V-belt air filter case cover
1. V-belt case air filter element
2
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1
1
Engine idling speed:1600–1800 r/min



PERIODIC MAINTENANCE AND ADJUSTMENT
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EAU21385
Checking the throttle grip free
playThe throttle grip free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
inner edge of the throttle grip. Periodi-
cally check the throttle grip free play
and, if necessary, have a Yamaha
dealer adjust it.
EAU21402
Valve clearanceThe valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU21879
TiresTires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be checked
and, if necessary, adjusted before each
ride.
WARNING
EWA10504
Operation of this vehicle with im-
proper tire pressure may cause se-
1. Throttle grip free play
1