2004 YAMAHA WHY 50 oil level

3
INSTRUMENT AND CONTROL FUNCTIONS
PUSH
OPEN
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Main switch/steering lock
The main switch/steering lock controls
the ignition and lighting systems, and
is used to lock the steering. The various
positions are described below.
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OFF “”
All electrical systems are off. The key
can be removed.
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CHECK “”
The 2-stroke engine oil level warning
light should come on. See page 3-2 for
an explanation of the engine oil level
warning light.
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LOCK “ ”
The steering is locked, and all electrical
systems are off. The key can be
removed.
To lock the steering
1. Turn the handlebars all the way to
the left.
2. Push the key in from the “
”
position, and then turn it to “
”
while still pushing it.
3. Remove the key.
To unlock the steering
Push the key in, and then turn it to “
”
while still pushing it.
EW000016
Never turn the key to “ ” or “ ”
while the scooter is moving, otherwise
the electrical systems will be switched
off, which may result in loss of control
or an accident. Make sure that the scoo-
ter is stopped before turning the key
to “ ” or “ ”.
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ON “ ”
All electrical circuits are supplied with
power, the taillight and meter lighting
come on, and the engine can be
started. The key cannot be removed.
NOTE :
The headlight comes on as soon as the
engine is started.
3-1

INSTRUMENT AND CONTROL FUNCTIONS
312ZAUM0184
1. Turn signal indicator light ""
2. High beam indicator light "
`"
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Turn signal indicator light ""
This indicator light flashes when the
turn signal switch is pushed to the left
or right.
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High beam indicator light ""
This indicator light comes on when the
high beam of the headlight is switched
on.
1
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1. Oil level indicator light ""
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Oil level warning light ""
This warning light comes on when the
key is in the "
" position or when the
oil level in the 2-stroke engine oil tank
is low during operation. If the warning
light comes on during operation, stop
immediately and fill the oil tank with
Yamalube 2 or equivalent 2-stroke
engine oil of either JASO grade "FC"
or ISO grades "EG-C" or "EG-D". The
warning light should go off after the 2-
stroke engine oil tank has been refilled.
NOTE :
If the warning light does not come on
when the key is in the "
" position or
does not go off after the 2-stroke engine
oil tank has been refilled, have a
Yamaha dealer check the electrical cir-
cuit.
EC000000
Do not operate the scooter until you
know that the engine oil level is
sufficient.
3-2
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Indicator and warning lights

INSTRUMENT AND CONTROL FUNCTIONS
3
2-stroke engine oil tank cap
To remove the 2-stroke engine oil tank
cap, pull it off.
To install the 2-stroke engine oil tank
cap, push it into the oil tank opening.
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Make sure that the fuel and 2-stroke
engine oil tank caps are properly
installed before riding the scooter.
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1
2
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1. Filler tube
2. Fuel level
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Fuel
Make sure that there is sufficient fuel
in the tank. Fill the fuel tank to the
bottom of the filler tube as shown.
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•Do not overfill the fuel tank,
otherwise it may overflow when
the fuel warms up and expands.
•Avoid spilling fuel on the hot
engine.
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EC000008
Immediately wipe off spilled fuel with
a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plas-
tic parts.
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Recommended fuel:
REGULAR UNLEADED
GASOLINE ONLY
Fuel tank capacity:
Total amount:
7.2 L
Your Yamaha engine has been
designed to use regular unleaded
gasoline with a research octane
number of 91 or higher. If knocking (or
pinging) occurs, use a gasoline of a
different brand or premium unleaded
fuel. Use of unleaded fuel will extend
spark plug life and reduce maintenance
costs.
3-6

PRE-OPERATION CHECKS
4
•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.
2-stroke engine oil•If necessary, add recommended oil to specified level. 3-5 — 3-7
•Check vehicle for oil leakage.
Final transmission oil•Check vehicle for oil leakage. 6-6
•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.
Rear brake•Check pedal free play. 3-5, 6-13 — 6-15
•Adjust if necessary.
•Make sure that operation is smooth.
Throttle grip•Check cable free play.
6-9, 6-15
•If necessary, have Yamaha dealer adjust cable free play
and lubricate cable and grip housing.
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.
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Pre-operation check list
ITEM CHECKS PAGE
4-1

OPERATION AND IMPORTANT RIDING POINTS
5
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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.
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Starting the engineEC000046
See page 5-4 for engine break-in ins-
tructions prior to operating the
vehicle for the first time.
1. Turn the key to "
", and 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. Close the throttle completely.3. While applying the front or rear
brake, start the engine by pushing
the start switch or by pushing the
kickstarter lever down.
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.
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PUSH
OPEN
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PERIODIC MAINTENANCE AND MINOR REPAIR
Periodic maintenance and lubrication chart ............ 6-2
Removing and installing the panel .......................... 6-5
Panel A .................................................................... 6-5
Checking the spark plug ......................................... 6-5
Final transmission oil .............................................. 6-6
Cleaning the air filter element ................................. 6-7
Adjusting the carburetor .......................................... 6-9
Adjusting the throttle cable free play ....................... 6-9
Tires ...................................................................... 6-10
Cast wheels .......................................................... 6-11
Adjusting the front brake lever free play ................ 6-12
Adjusting the front brake lever free play ................ 6-12
Checking the front brake pads .............................. 6-13
and rear brake shoes
Checking the brake fluid level ............................... 6-14
6 Changing the brake fluid ....................................... 6-15
Checking and lubricating the throttle grip .............. 6-15
and cable
Lubricating the front and rear brakes levers .......... 6-15
Checking and lubricating the centerstand ............. 6-16
Checking the front fork .......................................... 6-16
Checking the steering ........................................... 6-17
Checking the wheel bearings ................................ 6-17
Battery ................................................................... 6-18
Replacing the fuse ................................................ 6-19
Replacing a headlight bulb .................................... 6-20
Replacing the brake taillight bulb .......................... 6-21
Replacing a turn signal light bulb .......................... 6-21
Troubleshooting ..................................................... 6-22
Troubleshooting chart ............................................ 6-23

PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Checking the brake fluid
level
Insufficient brake fluid may allow air to
enter the brake system, possibly
causing it to become ineffective.
Before riding, check that the brake fluid
is above the minimum level mark and
replenish if necessary. A low brake fluid
level may indicate worn brake pads
and/or brake system leakage. If the
brake level is low, be sure to check the
brake pads for wear and the brake
system for leakage.Observe these precautions:
•When checking the fluid level,
make sure that the top of the
master cylinder is level by turning
the handlebars.
•Use only the recommended
quality brake fluid, otherwise the
rubber seals may deteriorate,
causing leakage and poor braking
performance.
Recommended brake fluid:
DOT 4
NOTE :
If DOT 4 is not available, DOT 3 can be
used.
•Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking performance.
•Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the fluid
and may result in vapor lock.
•Brake fluid may deteriorate
painted surfaces or plastic parts.
Always clean up spilled fluid
immediately.
•As the brake pads wear, it is nor-
mal for the brake fluid level to
gradually go down. However, if the
brake fluid level goes down
suddenly, have a Yamaha dealer
check the cause.
1
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1. Brake fluid level
6-14

PERIODIC MAINTENANCE AND MINOR REPAIR
6 To check the operation
1. Place the scooter on a level sur-
face and hold it in an upright po-
sition.
2. While applying the front brake,
push down hard on the
handlebars several times to check
if the front fork compresses and
rebounds smoothly.
EC000098
If any damage is found or the front
fork does not operate smoothly, have
a Yamaha dealer check or repair it.
6-16
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Checking the front fork
The condition and operation of the front
fork must be checked as follows at the
intervals specified in the periodic main-
tenance and lubrication chart.
To check the condition
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Securely support the scooter so that
there is no danger of it falling over.
Check the inner tubes for scratches,
damage and excessive oil leakage.
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Checking and lubricating the
centerstand
The operation of the centerstand should
be checked before each ride, and the
pivots and metal-to-metal contact sur-
faces should be lubricated if necessary.
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If the centerstand does not move up
and down smoothly, have a Yamaha
dealer check or repair it.
Recommended lubricant:
Lithium-soap-based grease
(all-purpose grease)
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