engine YAMAHA AEROX50 2004 User Guide

EAU00372
OPERATION AND IMPORTANT RIDING POINTS
Starting the engine .............................................................................. 5-1
Starting a warm engine ....................................................................... 5-2
Starting off ........................................................................................... 5-2
Acceleration and deceleration ............................................................. 5-3
Braking ................................................................................................ 5-3
Tips for reducing fuel consumption ..................................................... 5-4
Engine break-in ................................................................................... 5-4
Parking ................................................................................................ 5-5
5

OPERATION AND IMPORTANT RIDING POINTS
5
EAU01118
EW000129
•Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer
regarding any control or
function that you do not
thoroughly understand.
•Never start the engine or
operate it in a closed area for
any length of time. Exhaust fu-
mes are poisonous, and
inhaling them can cause loss of
consciousness and death
within a short time. Always
make sure that there is
adequate ventilation.
•For safety, always start the
engine with the centerstand
down.
WARNING
CAUTION:
CAUTION:
PUSH
OPEN
ZAUM0253
5-1
EAU00415*
Starting the engine
1. Turn the key to "", then when the
oil level warning light comes on,
turn it to "
".
EC000045
If the oil level warning light does not
come on, have a Yamaha dealer
check the electrical circuit.
2. Turn the starter (choke) on and
completely close the throttle. (See
page 3-9 for starter (choke)
operation.)3. Start the engine by pushing the
start switch or by pushing the
kickstarter lever down, while
applying the front or rear brake.
NOTE :
If the engine fails to start by pushing
the start switch, release the switch, wait
a few seconds, and then try again. Each
starting attempt should be as short as
possible to preserve the battery. Do not
crank the engine more than 5 seconds
on any one attempt. If the engine does
not start with the starter motor, try using
the kickstarter.
4. After starting the engine, move the
starter (choke) lever back halfway.
ECA00045
For maximum engine life, never
accelerate hard when the engine is
cold!

OPERATION AND IMPORTANT RIDING POINTS
5
EAU00433
Starting off
NOTE :
Before starting off, allow the engine to
warm up.
1. While pulling the rear brake lever
with your left hand and holding the
grab bar with your right hand,
push the scooter off the
centerstand.
2. Sit astride the seat, and then
adjust the rear view mirrors.
3. Switch the turn signal on.
4. Check for oncoming traffic, and
then slowly turn the throttle grip
(on the right) in order to take off.
5. Switch the turn signal off.
ZAUM0267
5-2
5. When the engine is warm, turn the
starter (choke) off.
NOTE :
The engine is warm when it responds
normally to the throttle with the starter
(choke) turned off.
EAU01258
Starting a warm engine
Follow the same procedure as for
starting a cold engine with the excep-
tion that the starter (choke) is not
required when the engine is warm.

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).

OPERATION AND IMPORTANT RIDING POINTS
5
EAU00461
Parking
When parking, stop the engine, and
then remove the key from the main
switch.
EW000058
•Since the engine and exhaust
system can become very hot,
park in a place where
pedestrians or children are not
likely to touch them.
•Do not park on a slope or on
soft ground, otherwise the
scooter may overturn.
EC000062
Never park in an area where there
are fire hazards such as grass or
other flammable materials.
WARNING
CAUTION:
5-5

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
EAU03453
Safety is an obligation of the owner.
Periodic inspection, adjustment and
lubrication will keep your vehicle in the
safest and most efficient condition pos-
sible. The most important points of
scooter inspection, adjustment, and
lubrication are explained on the
following pages.
EW000060
If you are not familiar with scooter
maintenance work, have a Yamaha
dealer do it for you.
EAU00466
EW000061
This scooter is designed for use on
paved roads only. If this scooter is
operated in abnormally dusty,
muddy or wet conditions, the air filter
element should be cleaned or
replaced more frequently, otherwise
rapid engine wear may result.
Consult a Yamaha dealer for proper
maintenance intervals.WARNING
WARNING
6-1

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
EAU01651
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
accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can
reveal the condition of the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the scooter is ridden
normally). If the spark plug shows a
distinctly different color, the engine
could be defective. Do not attempt to
diagnose such problems yourself.
Instead, have a Yamaha dealer check
the scooter.
If the spark plug shows signs of
electrode erosion and excessive carbon
or other deposits, it should be replaced.Specified spark plug:
BR8HS (NGK)
Before installing a spark plug, the spark
plug gap should be measured with a
wire thickness gauge and, if necessary,
adjusted to specification.
Spark plug gap:
0.5 — 0.7 mm
Clean the surface of the spark plug
gasket and its mating surface, and then
wipe off any grime from the spark plug
threads.
a
ZAUM0037
a Spark plug gap
Tightening torque:
Spark plug:
20 Nm (2.0 m
•kg)
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 possible.
6-6

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