2003 YAMAHA AEROX50 fuel

OPERATION AND IMPORTANT RIDING POINTS
5
EAU00436
Engine break-in
There is never a more important period
in the life of your engine than the period
between 0 and 1,000 km. For this
reason, you should read the following
material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1,000 km. The various parts in the
engine wear and polish themselves to
the correct operating clearances.
During this period, prolonged full-
throttle operation or any condition that
might result in engine overheating must
be avoided.
EAUT0003
0 — 150 km
Avoid operation above 1/3 throttle. Stop
the engine and let it cool for 5 to 10
minutes after every hour of operation.
Vary the speed of the scooter from time
to time. Do not operate it at one set
throttle position.150 — 500 km
Avoid prolonged operation above 1/2
throttle.
500 — 1,000 km
Avoid cruising speeds in excess of 3/
4 throttle.
ECAT0001
After 1,000 km of operation, be sure
to replace the final transmission oil.
1,000 km and beyond
Avoid prolonged full throttle operation.
Vary speeds occasionally.
EC000049
If any engine trouble should occur
during the engine break-in period,
immediately have a Yamaha dealer
check the vehicle.
CAUTION:
CAUTION:
5-4
EAU03093
Tips for reducing fuel
consumption
Fuel consumption depends largely on
your riding style. Consider the following
tips to reduce fuel consumption:
•Thoroughly warm up the engine.
•Avoid high engine speeds during
acceleration.
•Avoid high engine speeds with no
load on the engine.
•Turn the engine off instead of
letting it idle for an extended length
of time (e.g., in traffic jams, at
traffic lights or at railroad
crossings).

PERIODIC MAINTENANCE AND MINOR REPAIR
6
1 * Fuel line• Check fuel hoses and vacuum hose for cracks or damage.√√√√ √
2 Spark plug• Replace.√√√√ √
3 Air filter element• Clean.√√• Replace.√√
4 * Battery• Check electrolyte level and specific gravity.
√√√√ √
• Make sure that the breather hose is properly routed.
• Check operation, fluid level and vehicle for fluid leakage.
√√√√√ √
5 * Front brake(See NOTE on page 6-4.)
• Replace brake pads. Whenever worn to the limit
• Check operation, fluid level and vehicle for fluid leakage.
√√√√√ √
6 * Rear brake(See NOTE on page 6-4.)
• Replace brake pads. Whenever worn to the limit
7 * Brake hoses• Check for cracks or damage.√√√√ √• Replace. (See NOTE on page 6-4.) Every 4 years
8 * Wheels• Check runout and for damage.√√√√
EAU03686
Periodic maintenance and lubrication chart
NOTE :
•The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.
•From 30,000 km, repeat the maintenance intervals starting from 6,000 km.
•Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical skills.
ODOMETER READING (x 1,000 km)
NO. ITEMCHECK OR MAINTENANCE JOB
1
ANNUAL
CHECK
6121824
6-2

PERIODIC MAINTENANCE AND MINOR REPAIR
6
ZAUM0285ZAUM0286
EAU03218
Replacing a turn signal light
bulb
1. Remove the turn signal lens by
removing the screws.
2. Remove the defective bulb by
pushing it in and turning it
counterclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it
clockwise until it stops.
4. Install the lens by installing the
screws.
EC000108
Do not overtighten the screws,
otherwise the lens may break.
CAUTION:
EAU03087
Troubleshooting
Although Yamaha scooters receive a
thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems
yourself. However, should your scooter
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the scooter
properly.
Use only genuine Yamaha replacement
parts. Imitation parts may look like
Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
6-22

PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU03363
Troubleshooting charts
Starting problems or poor engine performance
EW000125
Keep away open flames and do not smoke while checking or working on the fuel system.
WARNING
Check the fuel level in
the fuel tank.
1. FuelThere is enough fuel.
There is no fuel.Check the compression.
Supply fuel.
Operate the electric starter.
2. CompressionThere is compression.
There is no compression.Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plugs
and check the electrodes.
3. IgnitionWet
DryWipe off with a dry cloth and correct the
spark plug gaps, or replace the spark plugs.
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. BatteryThe 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.The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the compressoin.
6-23

SCOOTER CARE AND STORAGE
7
•Do not use any harsh chemical
products on plastic parts. Be
sure to avoid using cloths or
sponges which have been in
contact with strong or abrasive
cleaning products, solvent or
thinner, fuel (gasoline), rust
removers or inhibitors, brake
fluid, antifreeze or electrolyte.
•Do not use high-pressure
washers or steam-jet cleaners
since they cause water
seepage and deterioration in
the following areas: seals (of
wheel and swingarm bearings,
fork and brakes), electric
components (couplers,
connectors, instruments,
switches and lights), breather
hoses and vents.
•For scooters equipped with a
windshield: Do not use strong
cleaners or hard sponges as
they will cause dulling or
scratching. Some cleaning
compounds for plastic may
leave scratches on the
windshield. Test the product on
a small hidden part of the
windshield to make sure that it
does not leave any marks. If the
windshield is scratched, use a
quality plastic polishing
compound after washing.
After normal use
Remove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottlebrush
for hard-to-reach areas. Stubborn dirt
and insects will come off more easily if
the area is covered with a wet cloth for
a few minutes before cleaning.
After riding in the rain, near the sea
or on salt-sprayed roads
Since sea salt or salt sprayed on the
roads during winter are extremely cor-
rosive in combination with water, carry
out the following steps after each ride
in the rain, near the sea or on salt-
sprayed roads.
NOTE :
Salt sprayed on roads in the winter may
remain well into spring.
1. Clean the scooter with cold water
and a mild detergent after the
engine has cooled down.
ECA00012
Do not use warm water since it
increases the corrosive action of the
salt.
2. Apply a corrosion protection spray
on all metal, including chrome-
and nickel-plated, surfaces to
prevent corrosion.
CAUTION:
7-2

SCOOTER CARE AND STORAGE
7 Long-term
Before storing your scooter for several
months:
1. Follow all the instructions in the
"Care" section of this chapter.
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 protect
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
sparking during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
EWA00003
To prevent damage or injury from
sparking, make sure to ground the
spark plug electrodes while turning
the engine over.
5. Lubricate all control cables and
the pivoting points of all levers and
pedals as well as of the sidestand/
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.
Alternatively, 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
excessively cold or warm place
(less than 0 °C or more than 30
°C). For more information on
storing the battery, see page 6-19.
NOTE :
Make any necessary repairs before
storing the scooter.
WARNING
7-4

SPECIFICATIONS
8
Specifications
Model YQ50
Dimensions:
Overall length 1.743 mm
Overall width 690 mm
Overall height 1.170 mm
Seat height 828 mm
Wheelbase 1.256 mm
Minimum ground clearance 185 mm
Minimum turning radius 1.800 mm
Basic weight:97 kg
(with oil and full fuel tank)
Engine:
Engine type Liquid cooled, 2 stroke
Cylinder arrangement Single cylinder, horizontal
Displacement 49.2 cc
Bore x stroke 40.0 x 39.2
Compression ratio 7.44:1
Starting system Electric and kick starter
Lubrication systemSeparate lubrication (Autolube)
Engine oil:
Type Yamalube 2
or 2 stroke engine oil
Recommended engine oil Jaso FC
classification or ISO EG-C, EG-D
Capacity 1.3 LFinal transmission oil:
Type SAE 10W30 type SE
Quantity 0.13L
Cooling system capacity:1.2L
(total amount)
Air filter type:Wet type element
Fuel:
Recommended fuel Regular unleaded gasoline
(RON 91 mini)
Fuel tank capacity 7L
Carburetor:
Manufacturer DELL'ORTO
Model/quantity PHBN 12HS x1
Spark plug:
Manufacturer/Model NGK / BR8HS
Spark plug gap 0.5—0.7 mm
Clutch type:Dry, centrifugal automatic
Transmission:
Primary reduction system Helical gear
Primary reduction ratio 52/13 (4.000)
Secondary reduction system Spur gear
Secondary reduction ratio 43/14 (3.071)
Transmission type V-belt automatic
Operation Centrifugal automatic type
8-1