hey i think i going buy my fiancee's 21th birthday. i want to buy him dirt bike. i don't know anything about this dirt bike.please let me know. my fiancee is smart and know what to do with it. but never had it before. he know what he doing. but please let me know. thanks..... which dirt bike i can buy for him? razor dirt bike? what do u think? which are the best? i am confused and don't know what can i get for him dirt bike?...thanks!!!!