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.
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.
5-4
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
8-1
Specifications
