First you have to understand that a motorcycle and car alternator are very different in operation.Jenik wrote: why not use higher capacity of stator? How the capacity of stator influence the CDI?
The typical motorcycle alternator uses permanent magnets and as a result, it's output is constant and always to the MAXIMUM. Any excess power not used in the lighting or ignition has to be "burned off" in the regulator as heat and wasted power.
The car alternator has a non-permanent magnet that is wound with wire to give a VARIABLE magnet and controllable output from zero to maximum. This means that the load on the engine is only enough to charge the battery and run the lights. (more efficient and less fuel used).
This means that the motorcycle alternator must be carefully matched to the electrical needs of the bike. If you add a larger unit without need for more wattage, you are just wasting precious engine power and fuel.






Thanks Mezo,