This has probally been talked about before but I need some help. I plan on doing woods racing or mx in the summer and I need some help with tires im running bald stock one now. I have my mind set on razrs. I ride mostly trails but like I said I want to start racing. My buddy has 18in razr mx but they seem to small and have very little ground clearence. I was kind of thinking of 20in razrs but I would like your input on size, Tire, and rim size. Thanks