Just a thought, make sure all stands and kill switches are correct, maybe you are doing something different when using kick start although I was unaware scooters of this size had kick start, also maybe power drain with electric is too much to produce spark thats a little out there but I always wondered. Are you checking that there is no spark by grounding plug out while trying to start electrically. Also change plug first it could be that simple, the gases in plug could be weak, the kick start will produce hotter spark sometimes.
