ZONGSHEN ZS125-86 Service Manual page 9

[3.]Gearshift
The gearshift changes the rotate speed and drive torque of the motorcycle transmission system and
ensures that the motorcycle has the appropriate traction and speed so as to adapt to regularly changing
driving conditions.
[4.]Rear Transmission Device
The rear transmission device transmits the power from the engine to rear whey further reducing the
rotate speed and increasing the torque, so as to drive the motorcycle. The rear transmission device of this
model adopts a chain drive.
4. Oil Supply System
The oil supply system regularly and quantitatively feeds a mixed gas prepared with clean gasoline
and air in proper proportion, according to different working conditions of the engine, into the combustion
chamber for combustion. The oil supply system mainly includes a fuel tank, fuel pump, fuel injector, fuel
filter and oil tube.
5. Electrical System
The electrical system provides electric energy to start and run the vehicle and emits a variety of
acoustic-optical signals to ensure safe and reliable driving. The electrical system generally includes a power
supply portion, an electricity consumption portion and a control portion.
[1.]Power Supply Portion
The power supply portion consists mainly of a generator (magneto) and a storage battery and other
components. When the engine drives the generator to reach a certain rotate speed, the generator outputs
electric energy. In addition that it supplies to electricity consumption equipment, it also charges the storage
battery. And the storage battery converts the stored chemical energy into electrical energy for consumption
by start devices, lamps and signal equipment.
[2.]Electricity Consumption Portion
The electricity consumption portion provides a variety of acoustic-optical signals to guarantee traffic
safety, while it also easily and rapidly starts the engine. The electricity consumption portion mainly
includes lamps, a signaler, and a electric starter.
[3.]Control Portion
The control portion guarantees and coordinates the normal operation of the power supply portion and
the electricity consumption portion. The control portion is mainly composed of a regulator, a rectifier, a
starting relay, a fuse protector (protective tube), a control switch and a main wire harness.
6. Engine
As the power source of the motorcycle, the engine is a power unit that makes the fuel burn in the
cylinder and converts the heat energy into mechanical energy. The overall structure of the engine consists
of a cylinder head, cylinder block, crankcase, piston group, crankshaft connecting rod group, valve train,
lubrication system, ignition system, cooling system and so on.
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