start with the spark plugs
Could be in need of a tune up.
The main cause of motorbike smoke is when the diesel is being burned and used in the engine. This smoke causes pollution to the environment.
Could be time for a tune up, spark plugs, wires, etc.
Lack of propulsion.
It is the alternator....
dirty fuel filter
you have a vacuum leak
Burning rubber, or screeching the tires, and then accelerating.
Cylinder miss.
The most common cause is slipping belt
unburnt fuel
Bad ignition coil