engine YAMAHA WHY 50 2003 Owner's Manual

PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Checking the wheel bearings
The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and
lubrication chart. If there is play in the
wheel hub or if the wheel does not turn
smoothly, have a Yamaha dealer check
the wheel bearings.
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2. Hold the lower ends of the front
fork legs and try to move them
forward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the
steering.
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Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Place a stand under the engine
to raise the front wheel off the
ground.
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Securely support the scooter so that
there is no danger of it falling over.

PERIODIC MAINTENANCE AND MINOR REPAIR
6
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Troubleshooting chartEW000125
Keep away open flames and do not smoke while checking or working on the fuel system.
Check the fuel level in
the fuel tank.
1. FuelThere is enough fuel.
There is no fuel.Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
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 plug
and check the electrodes.
3. IgnitionWipe 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.
Operate the electric starter.
4. BatteryThe engine turns over
quickly.
The engine turns over
slowly.The battery is good.
Check the battery lead connections,
and charge the battery if necessary.
Dry
WetOpen the throttle halfway and operate
the electric starter.
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SCOOTER CARE AND STORAGE
7
Care
While the open design of a scooter
reveals the attractiveness of the
technology, it also makes it more
vulnerable. Rust and corrosion can
develop even if high-quality
components are used. A rusty exhaust
pipe may go unnoticed on a car,
however, it detracts from the overall
appearance of a scooter. Frequent and
proper care does not only comply with
the terms of the warranty, but it will also
keep your scooter looking good, extend
its life and optimize its performance.
Before cleaning
1. Cover the muffler outlet with a
plastic bag after the engine has
cooled down.
2. Make sure that all caps and covers
as well as all electrical couplers
and connectors, including the
spark plug cap, are tightly
installed.3. Remove extremely stubborn dirt,
like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such
products onto seals, gaskets and
wheel axles. Always rinse the dirt
and degreaser off with water.
Cleaning
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•Avoid using strong acidic wheel
cleaners, especially on spoked
wheels. If such products are
used on hard-to-remove dirt, do
not leave the cleaner on the
affected area any longer than
instructed. Also, thoroughly
rinse the area off with water,
immediately dry it, and then
apply a corrosion protection
spray.
•Improper cleaning can damage
windshields, cowlings, panels
and other plastic parts. Use
only a soft, clean cloth or
sponge with mild detergent and
water to clean plastic.
•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, instru-
ments, switches and lights),
breather hoses and vents.
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SCOOTER CARE AND STORAGE
7
•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.
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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.After cleaning
1. Dry the scooter with a chamois or
an absorbing cloth.
2. Use a chrome polish to shine
chrome, aluminum and stainless-
steel parts, including the exhaust
system. (Even the thermally
induced discoloring of stainless-
steel exhaust systems can be
removed through polishing.)
3. To prevent corrosion, it is
recommended to apply a corro-
sion protection spray on all metal,
including chrome- and nickel-
plated, surfaces.
4. Use spray oil as a universal
cleaner to remove any remaining
dirt.
5. Touch up minor paint damage
caused by stones, etc.
6. Wax all painted surfaces.
7. Let the scooter dry completely
before storing or covering it.
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SCOOTER CARE AND STORAGE
7 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.
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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-
18.
NOTE :
Make any necessary repairs before
storing the scooter.
7-4

SPECIFICATIONS
8
Model YH50
Dimensions:
Overall length 1.940 mm
Overall width 685 mm
Overall height 1.105 mm
Seat height 765 mm
Wheelbase 1.294 mm
Minimum ground clearance 125 mm
Minimum turning radius 1.800 mm
Weight:
Wet (with oil and a full fuel tank) 78 kg
Engine:
Engine type Air cooled, 2 strokes
Cylinder arrangement Single cylinder, horizontal
Displacement 49.2 cm3
Bore x stroke 40.0 x 39.2
Compression ratio 7.25:1
Starting system type Electric and kick starter
Lubrication system Separate lubrication
(Autolube)
Engine oil:
Type Yamalube 2
or 2 strokes engine oil
Classification Jaso FC ou ISO EG-C, EG-D
Capacity 1.3 LTransmission oil:
Type SAE 10W30 type SE
Capacity
Périodic oil change 0.11L
Total amount 0.13L
Air filter type:Wet type element
Fuel:
Recommended fuel Regular unleaded gasoline
(RON 91 mini)
Fuel tank capacity 7L
Carburetor:
Type / quantity PY-12
Manufacturer GURTNER
Spark plug:
Type / Manufacturer BR8HS / NGK
Spark plug gap 0.6—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 45/12 (3.750)
Transmission type V-belt automatic
Operation Centrifugal automatic type
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Specifications

CONSUMER INFORMATION
9
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YOU ARE HEREBY REMINDED THAT MODIFICATIONS TO THE ENGINE OR THE POWER OF THE SCOOTER ARE
FORBIDDEN BY LAW.
ANY CHANGES FOR THE PURPOSE OF RAISING THE TOP SPEED OF THE VEHICLE OR BOOSTING THE POWER
OF THE ENGINE WOULD LEAD TO THE SCOOTER BEING
CLASSED AS A SCOOTER.
THIS WOULD REQUIRE THE OWNER:
•TO OBTAIN A NEW TYPE APPROVAL
•TO OBTAIN A SCOOTER REGISTRATION LICENSE
•TO HOLD A DRIVING LICENSE
IN ADDITION, SUCH CHANGES WOULD LEAD TO THE INVALIDATION OF TIE INSURANCE COVER, SINCE
INSURANCE POLICIES EXPLICITLY FORBID TECHNICAL CHANGES WHICH HAVE THE PURPOSE OF BOOSTING
THE PERFORMANCE.
FOR THE REASONS SET OUT ABOVE, A BREACH OF THE PROHIBITION TO TAMPER WITH THE ENGINE IS
PUNISHED BY LAW BY APPROPRIATE FINES INCLUDING THE CONFISCATION OF THE VEHICLE.
FINES ARE ALSO INFLICTED, ACCORDING TO CIRCUMSTANCES, FOR DRIVING WITHOUT A HELMET AND A
LICENSE PLATE, AS WELL AS FOR TAX EVASION (OMITTING TO PAY OWNERSHIP TAX).
DRIVING WITHOUT A DRIVING LICENSE IS A CRIMINAL OFFENSE.
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