Page 34 of 80

OPERATION AND IMPORTANT RIDING POINTS
5
EAU00435
Braking
1. Close the throttle completely.
2. Apply both front and rear brakes
simultaneously while gradually
increasing the pressure.
EW000057
•Avoid braking hard or suddenly
(especially when leaning over
to one side), otherwise the
scooter may skid or overturn.
ZAUM0269
•Railroad crossings, streetcar
rails, iron plates on road cons-
truction sites, and manhole
covers become extremely
slippery when wet. Therefore,
slow down when approaching
such areas and cross them with
caution.
•Keep in mind that braking on a
wet road is much more difficult.
Ride slowly down a hill, as
braking downhill can be very
difficult.
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).
5-3
Page 39 of 80

PERIODIC MAINTENANCE AND MINOR REPAIR
6
1 * Fuel line•Check fuel hoses and vacuum hose for cracks or damage.√√√√ √
2 Spark plug•Replace.√√√√ √
3 Air filter element•Clean.√√•Replace.√√
4 * Battery•Check electrolyte level and specific gravity.
√√√√ √
•Make sure that the breather hose is properly routed.
•Check operation, fluid level and vehicle for fluid leak
√√√√√ √
5 * Front brake(See NOTE on page 6-4.)
•Replace brake pads. Whenever worn to the limit
6 * Rear brake•Check operation and adjust brake lever free play.√√√√√ √•Replace brake shoes. Whenever worn to the limit
7 * Brake hose•Check for cracks or damage.√√√√ √•Replace. (See NOTE on page 6-4.) Every 4 years
8 * Wheels•Check runout and for damage.√√√√
EAU03686
Periodic maintenance and lubrication chart
NOTE :
•The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.
•From 30,000 km, repeat the maintenance intervals starting from 6,000 km.
•Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical skills.
ODOMETER READING (x 1,000 km)
NO. ITEMCHECK OR MAINTENANCE JOB
1
ANNUAL
CHECK
6121824
6-2
Page 59 of 80
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01008
Troubleshooting
Although Yamaha scooters receive a
thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting chart
represents a quick and easy procedure
for checking these vital systems
yourself. However, should your scooter
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the scooter
properly.
Use only genuine Yamaha replacement
parts. Imitation parts may look like
Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
6-22
Page 60 of 80

PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU01397
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.
6-23
Page 62 of 80

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
ECA00011
•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.
7-1
Page 64 of 80

SCOOTER CARE AND STORAGE
7
EWA00002
•Make sure that there is no oil
or wax on the brakes or tires. If
necessary, clean the brake
discs and brake linings with a
regular brake disc cleaner or
acetone, and wash the tires with
warm water and a mild
detergent.
•Before operating the scooter
test its braking performance
and cornering behavior.
ECA00013
•Apply spray oil and wax
sparingly and make sure to
wipe off any excess.
•Never apply oil or wax to any
rubber and plastic parts, but
treat them with a suitable care
product.
•Avoid using abrasive polishing
compounds as they will wear
away the paint.
NOTE :
Consult a Yamaha dealer for advice on
what products to use.
Storage
Short-term
Always store your scooter in a cool, dry
place and, if necessary, protect it
against dust with a porous cover.
ECA00015
•Storing the scooter in a poorly
ventilated room or covering it
with a tarp, while it is still wet,
will allow water and humidity to
seep in and cause rust.
•To prevent corrosion, avoid
damp cellars, stables (because
of the presence of ammonia)
and areas where strong
chemicals are stored.Long-term
Before storing your scooter for several
months:
1. Follow all the instructions in the
"Care" section of this chapter.
2. Drain the carburetor float chamber
by loosening the drain bolt; this will
prevent fuel deposits from building
up. Pour the drained fuel into the
fuel tank.
3. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
4. Perform the following steps to
protect the cylinder, piston rings,
etc. from corrosion.
7-3
Page 68 of 80

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