i was driving on a yamaha Sport 110ss(look like 110ss but inside using 100 part) motorcycle, about 70km/h for maybe 30min. when i heard the engine making a strange sound. then engine was off for few seconds, motorcycle was not stopped, then the engine self started again. battery is ok, full charged. piston and piston ring, Capacitor discharge ignition (CDI) is brand new. Alternator? any motorcycle expert here. Thank You.