My 1998 Polaris scrambler wont start but backfires like a **** every now when I try and pull and pull and pull start it and then I cleaned the carb out pretty well has spark and good compression but will run if I take off carb and spray premix into the boot between motor and carb seems like something's wrong with carb or fuel etc also I don't have the air box hooked up to the carb when I try to start I don't think that's a issue please help I purchased a carb rebuild kit its on the way May not getting fuel or too rich idk

 

Rebuild the carb and go from there. Process of elimination.Plus look close at the piston through the intake manifold. Broken piston skirts can do this also.