Add an aftermarket air-cleaner and go with a larger main jet, the exaust IMHO is a waste of cash unless your going to add the big bore kit, there is also two different kits available now. There is a 80cc kit which is actually only a 72cc and there is the big bore 80 kit which is a true 80cc. If you chose to go that route make sure you get the true 80 kit. but then you might have to ask someone here that has already done this ( i havent yet) as to which exaust to order if you do the upgrades..the 50cc or the 80cc? lol