Engine

The Coating Cylinder is to electroplate a layer of specialized coating material at the surface of combustion chamber, which holds the advantage of hardness and better heat evaporation efficiency, thus performs better resistance to friction ,and requires no more boring process. The advantage of Coating Cylinder are listed below:

1. lighter weight. 10%~25% ligher than conventional cylinder.
2. Better high temperature resistance, under fully lubrication, the Coating Cylinder can sustain the temperature over 1500 Celsius.
3. High friction resistance, the hardness is 2~3 times harder than conventional cylinder.
4. High heat evaporation efficiency, the combustion heat can travel to the cooling fin quickly.

The compression ratio of an internal combustion engine is the cylinder volume ratio between top dead center and bottom dead center (TDC & BDC). compression ratio = ( displacement + combustion chamber volume ) / combustion chamber volume.

The engine oil is the key material to lubricate the engine system, its crucial to use and exchange it periodically. The owner should use the specified type of oil regulated by the manufacturer, to fit the requirement of product warranty criteria. The frequency to check and exchange engine oil depends on descriptions shown on the owner's manual. But, its for sure that to perform checks and maintenance periodically would improve the product's performance and life.

The motorcycle engine used to be single cylinder-twin valve design. SYM unveiled its first single cylinder, 4-valve design engine in May, 1999. The main advantage of such new design is to increase the engine performance and efficiency during mid to high speed, make the performance far more superior then conventional twin valve design, especially acceleration, top speed and fuel efficiency aspects.

1. Blue Smoke: Abnormal engine oil cousumption, the bike should return to service center as soon as possible.
2. Black smoke: The fuel haven't been fully combusted, or false fuel / air mixture ratio.
3. If 2-stroke engine model been parked or driven under low speed for long time, the engine oil might accumulate largely in the exhaust pipe, causing vast white smoke. The solution is to ride at high speed for certain distance, or apply large throttle for a while, to burn out the accumulated engine oil and stop white smoke from emission.

The possible reasons are listed below.

1. The inappropriate adjustment of air/fuel mixture.
2. Slippage occurred in the clutch weights.
3. Oil leaking in the transmission box.
4. Severe frictional damage on the drive belt.

Although the engine oil of 4 stroke engine is circulative, there would be some loss of engine oil due to combustion.

1. The engine oil consumption. Never stop engine oil supply, when the engine oil warning light glows, Please supply 2 stroke engine oil as soon as possible.
2. Prevent long time parking. The engine oil might leak into the cylinder, causing diffuculty to start, or vast white smoke discharged during start up.
3. Don't travel under low speed, short range too often.

The superiority of EFi system are listed below.

1. Apparent cold start up improvement. (compare with carburetor models)
2. Lower emission.
3. Low fuel comsumption and hign effieciency.

To match the regulations of environmental protection, the fuel Evaporative Emission Control (EEC) system is now commonly installed. Such system was set at the top of fuel tank, to perform the function to prevent fuel vapor from emission, if the driver supply too much fuel or using side stand during refueling, the fuel might backflow to EEC and choke the air cleaner, causing difficulties to start the engine.

The acceleration may not be smooth due to cold started engine.

Especially the carburetor models. The driver should warm up the engine for 2-3 minutes after engine started if possible, to protect the engine.

If in rush, try not to apply large throttle suddenly if the bike just been started.

The letters means such engine oil's cold viscosity is 10, and 40 under high temperature.

The cooling liquid should be exchanged each year or every 10,000km.

The radiator cap should open after exchange, to ensure the air had been totally expelled, The coolant level would drop if air mix in pipe line after apply throttle slightly.

1. Too early igintion time.
2. Carbon deposited in the combustion chamber.
3. Excessive compression ratio.
4. Improper fuel type is supplied.

1. Supply regulated fuel type.
2. Never modify the engine.
3. Clean the accumulated carbon in the combustion chamber periodically.

1. Use quality-assured fuel.
2. Exchange engine oil periodically.
3. Inspect or exchange air cleaner element according to operating environment.

1. Never apply large throttle when engine has no workload.
2. Any electrical modification is strictly prohibited.
3. In order to keep sufficient power supply, check battery every 2,000km.
4. Clean the throttle and injection nozzle every 3,000~5,000 km.

The CVT transmission system functions through the drive belt. The ash of belt and dust might accumulate on front or back pulley due to rubbing, so the transmission system should be cleaned every 3,000km, or there might be slippage at drive belt or rear driven pulley.