2003 YAMAHA AEROX50 transmission

2
DESCRIPTION
Left view
1. Rear brake lever (page 3-5, 6-13, 6-16)
2. Left handlebar switches (page 3-4)
3. Speedometer (page 3-3)
4. Main switch/steering lock (page 3-1, 3-9)
2-1
1
23
4
68
7
5
5. Final transmission oil filler cap (page 6-7)
6. Centerstand (page 6-16)
7. Kick starter (page 3-7)
8. Air filter (page 6-9)

PRE-OPERATION CHECKS
4
EAU03439
Pre-operation check list
ITEM CHECKS PAGE
• Check fuel level in fuel tank.
Fuel• Refuel if necessary. 3-5 — 3-6
• Check fuel line for leakage.
• Check oil level in oil tank.
Two-stroke engine oil• If necessary, add recommended oil to specified level. 3-8, 6-15
• Check vehicle for oil leakage.
Final transmission oil• Check vehicle for oil leakage. 6-7
• Check coolant level in reservoir.
Coolant• If necessary, add recommended coolant to specified level. 6-8
• Check cooling system for leakage.
• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
Front brake• Check fluid level in reservoir. 3-5, 6-13 — 6-15
• If necessary, add recommended brake fluid to specified level.
• Check hydraulic system for leakage.
• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
Rear brake• Check fluid level in reservoir. 3-5, 6-13 — 6-15
• If necessary, add recommended brake fluid to specified level.
• Check hydraulic system for leakage.
The condition of a vehicle is the owner’s responsibility. Vital components can start to deteriorate quickly and unexpectedly,
even if the vehicle remains unused (for example, as a result of exposure to the elements). Any damage, fluid leakage or
loss of tire air pressure could have serious consequences. Therefore, it is very important, in addition to a thorough visual
inspection, to check the following points before each ride.
4-1

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).

EAU00462
PERIODIC MAINTENANCE AND MINOR REPAIR
Periodic maintenance and lubrication chart ............ 6-2
Removing and installing cowling and panel ............ 6-5
Cowling A ................................................................ 6-5
Panel A .................................................................... 6-5
Checking the spark plug ......................................... 6-6
Final transmission oil .............................................. 6-7
Coolant .................................................................... 6-8
Cleaning the air filter element ................................. 6-9
Adjusting the carburetor ........................................ 6-10
Adjusting the throttle cable free play ..................... 6-11
Tires ...................................................................... 6-11
Wheels .................................................................. 6-13
Adjusting the front and rear brake lever
free play ................................................................ 6-13
Checking the front and rear brake pads ................ 6-14
Checking the brake fluid level ............................... 6-14
6 Changing the brake fluid ....................................... 6-15
Adjusting the autolube pump ................................ 6-15
Checking and lubricating the cables ..................... 6-16
Lubricating the front and rear brakes levers .......... 6-16
Checking and lubricating the centerstand ............. 6-16
Checking the front fork .......................................... 6-17
Checking the steering ........................................... 6-17
Checking the wheel bearings ................................ 6-18
Battery ................................................................... 6-18
Replacing the fuse ................................................ 6-20
Replacing a headlight bulb .................................... 6-20
Replacing tail/brake light bulb ............................... 6-21
Replacing a turn signal light bulb .......................... 6-22
Troubleshooting ..................................................... 6-22
Troubleshooting chart ............................................ 6-23
Engine overheating ............................................... 6-24

PERIODIC MAINTENANCE AND MINOR REPAIR
6
• Check tread depth and for damage.
9 * Tires• Replace if necessary.
√√√√ √
• Check air pressure.
• Correct if necessary.
10 * Wheel bearings• Check bearing for looseness or damage.√√√√
11 * Steering bearings• Check bearing play and steering for roughness.√√√√√• Lubricate with lithium-soap-based grease. Every 24,000 km
12 * Chassis fasteners• Make sure that all nuts, bolts and screws are
√√√√ √
properly tightened.
13 Centerstand• Check operation.
√√√√ √
• Lubricate.
14 * Front fork• Check operation and for oil leakage.√√√√
15 * Shock absorber assembly• Check operation and shock absorber for oil leakage.√√√√
16 * Carburetor• Check starter (chocke) operation.
√√√√√ √
• Adjust engine idling speed.
17 * Autolube pump• Check operation.
√√√√
• Bleed if necessary.
18 Final transmission oil• Check vehicle for oil leakage.√√ √• Change.√√√
19 * V-belt• Replace. Every 10,000 km
20 * Front and rear brake
• Check operation.√√√√√ √
switches
ODOMETER READING (x 1,000 km)
NO. ITEMCHECK OR MAINTENANCE JOB
1
ANNUAL
CHECK
6121824
6-3

PERIODIC MAINTENANCE AND MINOR REPAIR
6
EWA00062
•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.
WARNING
EAU04228
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 it up by
riding the scooter for several mi-
nutes, and then stop the engine.2. Place the scooter on the
centerstand.
3. Place an oil pan under the final
transmission case to collect the
used oil.
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.
Tightening torque:
Final transmission oil drain bolt:
18 Nm (1.8 m
•kgf)
6. Add the specified amount of the
recommended final transmission
oil, and then install and tighten the
oil filler cap.
Recommended final transmission
oil:
See page 8-1.
Oil quantity:
0.13 L
12ZAUM0273
1. Final transmission oil drain bolt
2. Oil filler cap
6-7

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