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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.

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.

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

The fuel consumption rates declared by SYM are based on laboratory experiments.

The condition of those experiments are quite different from daily on-road use, which are affected by driver's weight, road condition, speed, tire pressure and driving habits.

Generally, the consumption difference gap between 20%~30% is acceptable.

The 2 stroke engine oil would mix with fuel to lubricate the engine system, then burn with fuel together.

If the engine oil warning light glows, the engine oil should be supplied as soon as possible to prevent engine from seizing.

The 4 stroke engine oil is contained in the crank case, must be exchanged every specified mileage noticed in the manual.

The key point is to keep sufficient volume of engine oil, so the driver should recharge or exchange the engine oil if needed.

1. Read manual carefully to understand all equipments, functions and notices.
2. Knowing the owner's equality via reading warranty criteria.
3. Never modify the bike to avoid damage or warranty uncovered, especially the electrical and engine system.
4. Never disassemble the bike by self.
5. Carry owner's manual onboard, in order to contact service center while breakdown.
6. Perform periodical maintenance schedule noticed by owner's manual, especially the engine oil, gear oil and air cleaner.
7. Get used to warm up the bike, also avoid to apply throttle suddenly.
8. Return to service center as soon as possible if abnormalities are found.
9. Use SYM Genuine spare parts to ensure quality and safety.

The conventional engine oil is produced during petroleum refining process, so called the mineral engine oil.
The synthetical oil is chemical proccessed conventional engine oil, some manufacturer would add some extra additives, to increase its lubrication and other positive performance.
Both kinds of oil are suitable for engine lubrication, but synthetical oil would have better performance for durability and so on. The price of synthetical oil is higher too.

The motorcycle electric generating system contains:

1. ACG(AC Generator): To generate all electric power demanded by whole motorcycle.
2. REG. REC.: To transform the AC power generated by ACG into DC power, regulate the power supply.
3. Battery: To store the electric power generated by ACG, and to supply power requirements of start motor.

There are several possible causes:

1. The daily driven distance is too short.
2. The bike is parked for too long time.
3. Often operated under low speed.
4. Components within electrical recharging system had failed.
5. Overload or broken caused by private electrical modification.
6. Poor battery quality.

1. Poor light bulb quality, or inappropriate electrical watts supply.
2. Plating layer had came off from the reflection surface, or lamp housing deteriorated.
3. Poor commutator quality. (For AC lighting models)
4. Insufficient battery power supply. (For DC lighting models)
5. The coil of generator had failed, causing insufficient power supply.

The ABS is an abbreviation of Anti-lock braking systems. It is an active safety braking system for vehicles features designed to help drivers retain steering control by preventing wheels from locking up during an episode of heavy braking.

ABS is designed to help prevent the wheel from locking up when hard brakes are applied while running straight. The ABS automatically regulates brake force. Intermittently gaining gripping force and braking force helps prevent wheel lock-up and allows stable steering control while stopping.

1. Brake pads are too hard.
2. Caliper deformed.
3. Cushion and caliper are not parallel.
4. Morning effect. If disk brake left without using for a certain time, the pad would absorb the mist,  causing harshness when braking. This situation would be eased after several times of use.
5. Something hard jammed the brake pad.

The air cleaner should be exchanged every 3000~5000km under normal operation.

If the vehicle operates in dusty environment, the checking frequency should be increased, and replace air cleaner element if necessary to prevent engine failure.

The manuals shows significant notices to increase checking frequency for inspection or clean/exchange air cleaner element depends on the operating environment.

The filtration efficiency of air cleaner is crucial to it's performance, efficiency and durability of an engine, so the manufacturer would list the air cleaner as a periodical check or exchange item.

The frequency to check air cleaner should be increased if operated in dusty enviroment, to prevent engine break down.

The Combined Brake System (CBS) is a brand-new way of scooter braking solely developed by SYM. The tradition way of scooter braking is to pull the brake lever through both hands.

Because the throttle and front wheel brake are both operated by right hand, thus insufficient braking force might be applied during emergency, even cause slip and fall at rear wheel.

The CBS system take a joint way to apply braking, when driver pull the brake lever, brakes of both wheels would be activated at the same time, to sustain the stability during emergency braking.

The structure of CBS system is rather complicated, if any abnormal situation of CBS system appeared, please return to the service center as soon as possible. The adjustments must be performed by technician, any unprofessional adjustments may be extremely dangerous and is strictly prohibited.

Due to oil tank design, road condition, driving status and so on, the performance of fuel indicator is not always appeared in linear way. Some types has special consideration that main and secondary fuel tank is installed, but the sensor is set in main tank, causing the indicator needle standing still before certain mileage.

So, take the fuel indicator as a reference, then calculate the fuel quantity consumed after each refueling, also keep the indicator needle above the low fuel warning line, thus to keep the motorcycle from out of fuel.

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.

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.

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

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

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

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.

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