Motorcycle Repair: spark plug gap, spark plug gap, honda 250

Question
my bike (honda 250 r 3 wheeler) only starts when i pull start it and then i have to keep giving it gas to keep it running?is it possible  wrong spark plug gap? If not any ideas?

Answer
very possible but it could also be a bad magneto,staor acting up take off side cover of engine pull magneto out sand it lightly also clean armature inside this should help you. if you need more info im here ok. i cant remember if this model had points are not if so they are the problem.

  mitch