YAMAHA MAJESTY 125 2008 Service Manual

EAU18771
Removing and installing
panels
1. Panel A
2. Panel B
The panels shown need to be remo-
ved to perform some of the mainte-
nance jobs described in this chapter.
Refer to this section each time a
panel needs to be removed and insta-
lled.
EAU19210
Panel A
1. Panel A
To remove the panel
Remove the screws, and then take
the panel off.
1. Screw
To install the panel
Place the panel in the original posi-
tion, and then install the screws.
Panel B
1. Panel B
To remove the panel
Remove the screw, and then take the
panel off.
1. Screw
1
1
1
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2
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To install the panel
Place the panel in the original posi-
tion, and then install the screw.
EAU19603
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 maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
To remove the spark plug
1. Spark plug cap
1. Remove the spark plug cap.
1. Spark plug wrench
2. Remove the spark plug as
shown, with the spark plug
wrench included in the owner’s
tool kit.
To check the spark plug
1. Check that the porcelain insula-
tor around the center electrode of
the spark plug is a medium-to-
light tan (the ideal color when the
vehicle is ridden normally).
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1
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NOTE:
If the spark plug shows a distinctly
different color, the engine could be
operating improperly. Do not attempt
to diagnose such problems yourself.
Instead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electro-
de erosion and excessive carbon
or other deposits, and replace it if
necessary.To install the spark plug
1. Spark plug gap
1. Measure the spark plug gap with
a wire thickness gauge and, if
necessary, adjust the gap to spe-
cification.
2. Clean the surface of the spark
plug gasket and its mating surfa-
ce, and then wipe off any grime
from the spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then
tighten it to the specified torque.
NOTE:
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 pos-
sible.
4. Install the spark plug cap.
Tightening torque:
Spark plug:
20 Nm (2.0 m•kgf, 14.5 ft•lbf)
Spark plug gap:
0.7 ~ 0.8 (0.02 ~ 0.03 in)
1
ZAUM0037
Specified spark plug:
NGK (CR8E)
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EAUM1260
Engine oil
The engine oil level should be chec-
ked before each ride. In addition, the
oil must be changed at the intervals
specified in the periodic maintenance
and lubrication chart
and when the oil change indicator
display comes on.
To check the engine oil level
1. Place the scooter on the centers-
tand.
NOTE:
Make sure that the scooter is positio-
ned straight up when checking the oil
level. 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.
1. Engine oil filler cap
3. Wait a few minutes until the oil
settles, remove the oil filler cap,
wipe the dipstick clean, insert it
back into the oil filler hole (wit-
hout screwing it in), and then
remove it again to check the oil
level.
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
NOTE:
The engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to rai-
se 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
1. Start the engine, warm it up for
several minutes, and then turn it
off.
1
2
3
4
1
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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 bolt to
drain the oil from the crankcase.
1. Engine oil drain bolt
2. Washer
4. Check the washer for damage
and replace it if necessary.
5. Install the washer and the engine
oil drain bolt, and then tighten the
drain bolt to the specified torque.
NOTE:
Make sure that the washer is properly
seated.
6. Add the specified amount of the
recommended engine oil, and
then install and tighten the oil
filler cap.
ECA11670
CAUTION:
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 CONSER-
VING II” or higher.
Be sure no foreign material
enters the crankcase.
7. Start the engine, and then let it
idle for several minutes while
checking it for oil leakage. If oil is
leaking, immediately turn the
engine off and check for the cau-
se.
8. Reset the oil change indicator
display according to the follo-
wing procedure.
To reset the oil change indicator
display
1. Push and hold the "TRIP" button
for a MAXIMUM of three
seconds. While pushing the
"TRIP" button, turn the key to
"f".
Recommended engine oil:
See page 8-1.
Oil change quantity:
1.2 L (1.27 US qt) (1.06 Imp.qt)
Tightening torque:
Engine oil drain bolt:
32 Nm (3.2 m•kgf, 23.1 ft•lbf)
2
1
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2. Release the "TRIP" button and
the oil change indicator light will
go off.
3. Turn the key to "e".
NOTE:
If the engine oil is changed before the
oil change indicator light comes on
(i.e. before the periodic oil change
interval has been reached), the indi-
cator light must be reset after the oil
change for the next periodic oil chan-
ge to be indicated at the correct time.
To reset the oil change indicator light
before the periodic oil change interval
has been reached, follow the above
procedure, but note that the indicator
light will come on for 1.4 seconds
after releasing the reset button, other-
wise repeat the procedure.
EAU20061
Final transmission oil
The 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 trans-
mission 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 centers-
tand.
3. Place an oil pan under the final
transmission case to collect the
used oil.
1. Final trasmission oil filler cap
1. Final transmission oil drain bolt
4. Remove the oil filler cap and
drain bolt to drain the oil from the
final transmission case.
5. Install the final transmission oil
drain bolt, and then tighten it to
the specified torque.
1
1
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6. Add the specified amount of the
recommended final transmission
oil, and then install and tighten
the oil filler cap.
EWA11310
s s
WARNING
Make sure that no foreign
material enters the final trans-
mission case.
Make sure that no oil gets on
the tire or wheel.
7. Check the final transmission case
for oil leakage. If oil is leaking,
check for the cause.
EAU20070
Coolant
The coolant level should be checked
before each ride. In addition, the coo-
lant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU20101
To check the coolant level
1. Place the vehicle on the centers-
tand.
NOTE:
The coolant level must be chec-
ked on a cold engine since the
level varies with engine tempera-
ture.
Make sure that the vehicle is
positioned straight up when
checking the coolant level. A
slight tilt to the side can result in
a false reading.
1. Maximum level mark
2. Minimum level mark
2. Check the coolant level in the
coolant reservoir.
NOTE:
The coolant should be between the
minimum and maximum level marks.
Recommended final transmission
oil:
See page 8-1.
Oil quantity:
0.15 L (0.16 US qt) (0.88 Imp.qt)
Tightening torque:
Final transmission oil drain bolt:
22 Nm (2.2 m•kgf, 15.9 ft•lbf)
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1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
3. If the coolant is at or below the
minimum level mark, remove
panel A (See page 6-6.), remove
the reservoir cap, add coolant to
the maximum level mark, and
then install the reservoir cap and
the panel.
ECA10470
CAUTION:
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 coolant, replace it with coo-
lant as soon as possible, other-
wise the engine may not be
sufficiently cooled and the coo-
ling system will not be protec-
ted against frost and corrosion.
If water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content of
the coolant as soon as possi-
ble, otherwise the effective-
ness of the coolant will be
reduced.
EWA10380
s s
WARNING
Never attempt to remove the radia-
tor cap when the engine is hot.
NOTE:
The radiator fan is automatically
switched on or off according to
the coolant temperature in the
radiator.
If the engine overheats, see page
6-33 for further instructions.
EAU33030
Changing the coolantEWA10380
s s
WARNING
Never attempt to remove the radia-
tor cap when the engine is hot.
The coolant must be changed at the
intervals specified in the periodic
maintenance and lubrication chart.
Have a Yamaha dealer change the
coolant.
Coolant reservoir capacity (up to
the maximum level mark):
0.30 L (0.32 US qt) (0.26 Imp.qt)
12
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EAUM1320
Air filter and V-belt case air
filter elements
The air filter and the V-belt case air fil-
ter elements should be cleaned at the
intervals specified in the periodic
maintenance and lubrication chart.
Clean both filter elements more fre-
quently if you are riding in unusually
wet or dusty areas.
Cleaning the air filter element
1. Place the scooter on the centers-
tand.
1. Screw
2. Air filter case cover
2. Remove the air filter case cover
by removing the screw.
1. Air filter element
3. Pull the air filter element out.
4. Lightly tap the air filter element to
remove most of the dust and dirt,
and then blow the remaining dirt
out with compressed air.
5. Check the air filter element for
damage and replace it if neces-
sary.6. Insert the air filter element into
the air filter case.
7. Install the air filter case cover by
installing the screw.
Cleaning the V-belt case air filter
element
1. Screw
2. V-belt case air filter cover
1. Remove the V-belt case air filter
cover by removing the screws.
1. Air filter element
1
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2
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2. Remove the air filter element, and
then blow out the dirt with com-
pressed air as shown.
3. Check the air filter element for
damage and replace it if neces-
sary.
4. Install the air filter element with
the colored side facing outward.
5. Install the V-belt case air filter
cover by installing the screws.
ECA10530
CAUTION:
Make sure that each filter ele-
ment is properly seated in its
case.
The engine should never be
operated without the filter ele-
ments installed, otherwise the
piston(s) and/or cylinder(s)
may become excessively worn.
EAU21300
Adjusting the carburetor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, all car-
buretor adjustments should be left to
a Yamaha dealer, who has the neces-
sary professional knowledge and
experience.
EAU21370
Adjusting the throttle cable
free play
The throttle cable free play should
measure 4 ~ 6 mm (0.15 ~ 0.24 in) at
the throttle grip. Periodically check
the throttle cable free play and, if
necessary, adjust it as follows.
NOTE:
The engine idling speed must be
correctly adjusted before checking and
adjusting the throttle cable free play.
1. Throttle cable free play
2. Locknut
3. Adjusting nut
1. Loosen the locknut.
2. To increase the throttle cable free
play, turn the adjusting nut in
1 a
b
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