My sportster has been having issues,sometimes before i start it ive gotta smack the headlight and it will start right up,and it will shut off sometimes when im going down the road and same thing when i smack it,it will start back up.could it be a short with the start and off switch or something else,ive never messed with wiringso i need help,thanks

 

smack the headlight?

sounds to me like you're losing electrical power somewhere. have you tested the kill switch? that would be the place to start if it were I