My friend wants to buy a 85cc mx-bike. Wich one of the 85's is the most powerfull/fastest? He's 25 yrs old and want's a small bike to "play around with". He asked me to look into it but i'm thinkin he'd be better of with a kx100; it's still small but a little more powerfull, right? Any comments would be appreciated. Excuse my bad english.