PERIODIC MAINTENANCE AND ADJUSTMENT
6-7
6
EAU19622
Checking the spark plug The spark plug is an important engine
component, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode, it
should be removed and checked in ac-
cordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
The porcelain insulator around the cen-
ter electrode of the spark plug should
be a medium-to-light tan (the ideal color
when the vehicle is ridden normally). If
the spark plug shows a distinctly differ-
ent color, the engine could be operating
improperly. Do not attempt to diagnose
such problems yourself. Instead, have
a Yamaha dealer check the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon or
other deposits, it should be replaced.Before installing a spark plug, the spark
plug gap should be measured with a
wire thickness gauge and, if necessary,
adjusted to specification.
Clean the surface of the spark plug
gasket and its mating surface, and then
wipe off any grime from the spark plug
threads.
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.
Specified spark plug:
NGK/BR8HS
1. Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
20 Nm (2.0 m·kgf, 14 ft·lbf)
1
ZAUM0037
U1PHE0E0.book Page 7 Wednesday, August 29, 2012 4:42 PM
PERIODIC MAINTENANCE AND ADJUSTMENT
6-8
6
EAU20066
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 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.5. 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 entersthe final transmission case.
Make sure that no oil gets on the
tire or wheel.
[EWA11311]
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.
1. Final transmission oil drain bolt
2. Final transmission oil filler capTightening torque:
Final transmission oil drain bolt:
18 Nm (1.8 m·kgf, 13 ft·lbf)
12
ZAUM0273
Recommended final transmission
oil:
See page 8-1.
Oil quantity:
0.11 L (0.12 US qt, 0.10 Imp.qt)
U1PHE0E0.book Page 8 Wednesday, August 29, 2012 4:42 PM
PERIODIC MAINTENANCE AND ADJUSTMENT
6-9
6
EAU20070
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.
EAUM2102
To 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 temperature.
●
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 through
the check window.TIPThe coolant should be between the
minimum and maximum level marks.
3. If the coolant is at or below the
minimum level mark, remove the
cowling A. (See page 6-6.)
4. Open the reservoir cap, and then
add coolant to the maximum level
mark. WARNING! Remove only
the coolant reservoir cap. Never
attempt to remove the radiator
cap when the engine is hot.
[EWA15161]
NOTICE: 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 cool-
ant as soon as possible, other-wise the cooling system will not
be protected against frost and
corrosion. If water has been
added to the coolant, have a
Yamaha dealer check the anti-
freeze content of the coolant as
soon as possible, otherwise the
effectiveness of the coolant will
be reduced.
[ECA10472]
5. Close the reservoir cap, and then
install the cowling.
1. Maximum level mark
2. Minimum level mark
1
2
ZAUM0591
1. Coolant reservoir cap
Coolant reservoir capacity:
0.25 L (0.26 US qt, 0.22 Imp.qt)1ZAUM0274
U1PHE0E0.book Page 9 Wednesday, August 29, 2012 4:42 PM
PERIODIC MAINTENANCE AND ADJUSTMENT
6-11
6
TIPThe air filter element should be wet but
not dripping.4. Insert the element into the air filtercase. NOTICE: Make sure that
the air filter element is properly
seated in the air filter case. The
engine should never be operat-
ed without the air filter element
installed, otherwise the pis-
ton(s) and/or cylinder(s) may
become excessively worn.
[ECA10481]
5. Install the air filter case cover by in- stalling the screws.
EAU21300
Adjusting the carburetor The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, all carbu-
retor adjustments should be left to a
Yamaha dealer, who has the neces-
sary professional knowledge and expe-
rience.
EAU21384
Checking the throttle grip free
play The 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 deal-
er adjust it.
Recommended oil:Foam air filter oil
1. Throttle grip free play1ZAUM0051
U1PHE0E0.book Page 11 Thursday, September 6, 2012 3:31 PM
PERIODIC MAINTENANCE AND ADJUSTMENT
6-26
6
EAU37622
Troubleshooting charts Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is
enough fuel.
There is
no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the
electric starter or the
kickstarter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wet
Dry
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start. Have a
Yamaha dealer check the vehicle.The engine does not start.
Check the battery.Open the throttle halfway and
operate the electric starter.
Operate the
electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the electrolyte and battery
lead connections, and charge the
battery if necessary.
U1PHE0E0.book Page 26 Wednesday, August 29, 2012 4:42 PM
PERIODIC MAINTENANCE AND ADJUSTMENT
6-27
6 Engine overheating
WARNING
EWA10400
●
Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
●
After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the hissing
sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended coolant
as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
U1PHE0E0.book Page 27 Wednesday, August 29, 2012 4:42 PM
SCOOTER CARE AND STORAGE
7-4
7 2. Drain the carburetor float chamber
by loosening the drain bolt; this will
prevent fuel deposits from building
up. Pour the drained fuel into the
fuel tank.
3. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
4. Perform the following steps to pro-
tect the cylinder, piston rings, etc.
from corrosion.
a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine oil
into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
WARNING! To prevent dam-
age or injury from sparking,
make sure to ground thespark plug electrodes while
turning the engine over.
[EWA10951]
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
5. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.
6. Check and, if necessary, correct
the tire air pressure, and then lift
the scooter so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
7. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
8. Remove the battery and fully
charge it. Store it in a cool, dry
place and charge it once a month.
Do not store the battery in an ex-
cessively cold or warm place [less
than 0 °C (30 °F) or more than 30°C (90 °F)]. For more information
on storing the battery, see page
6-19.
TIPMake any necessary repairs before
storing the scooter.
U1PHE0E0.book Page 4 Wednesday, August 29, 2012 4:42 PM
INDEX22-stroke engine oil................................. 3-10AAcceleration and deceleration................. 5-2
Air filter element, cleaning..................... 6-10
Auxiliary light bulb, replacing
(if equipped)........................................ 6-24BBattery................................................... 6-19
Brake fluid, changing ............................ 6-16
Brake fluid level, checking .................... 6-15
Brake lever, front..................................... 3-7
Brake lever, rear ..................................... 3-7
Brake levers, lubricating........................ 6-17
Braking .................................................... 5-2CCarburetor,adjusting ............................. 6-11
Care ........................................................ 7-1
Catalytic converter ................................ 3-10
Centerstand, checking and
lubricating ........................................... 6-17
Coolant.................................................... 6-9
Coolant temperature warning light .......... 3-3
Cowling and panel, removing and
installing................................................ 6-6DDimmer switch ........................................ 3-7EEngine break-in ....................................... 5-3FFinal transmission oil .............................. 6-8
Front and rear brake lever free play,
checking ............................................. 6-14
Front and rear brake pads, checking .... 6-15Front fork, checking .............................. 6-18
Fuel......................................................... 3-9
Fuel and 2-stroke engine oil tank caps ... 3-8
Fuel consumption, tips for reducing........ 5-3
Fuel level warning light ........................... 3-3
Fuse, replacing ..................................... 6-21
HHandlebar switches ................................ 3-6
Headlight bulb, replacing ...................... 6-22
High beam indicator light ........................ 3-2
Horn switch ............................................. 3-7IIdentification numbers ............................ 9-1
Indicator lights and warning light ............ 3-2KKickstarter............................................. 3-11LLicense plate light ................................. 6-24MMain switch/steering lock........................ 3-1
Maintenance and lubrication, periodic .... 6-3
Maintenance, emission control
system .................................................. 6-2
Matte color, caution ................................ 7-1
Model label ............................................. 9-1
Multi-function display (NS50).................. 3-4OOil level warning light.............................. 3-2PParking ................................................... 5-4
Part locations .......................................... 2-1SSafe-riding points.................................... 1-5
Safety information................................... 1-1Seats ..................................................... 3-11
Shock absorber assembly,
adjusting (if equipped) ........................ 3-13
Spark plug, checking ............................... 6-7
Specifications .......................................... 8-1
Speedometer unit (NS50N) ..................... 3-3
Starting a cold engine ............................. 5-1
Starting off ............................................... 5-2
Start switch.............................................. 3-7
Steering, checking................................. 6-19
Storage.................................................... 7-3
Storage compartment............................ 3-12
TTail/brake light bulb, replacing .............. 6-23
Throttle grip and cable, checking and
lubricating ........................................... 6-17
Throttle grip free play, checking ............ 6-11
Tires ...................................................... 6-12
Troubleshooting .................................... 6-25
Troubleshooting charts.......................... 6-26
Turn signal indicator light ........................ 3-2
Turn signal light bulb, replacing ............ 6-23
Turn signal switch ................................... 3-7VVehicle identification number .................. 9-1WWheel bearings, checking ..................... 6-19
Wheels .................................................. 6-14
U1PHE0E0.book Page 1 Wednesday, August 29, 2012 4:42 PM