Hi, I am currently in the market of buying a track bike. Just wondering what are the major differences between the 2000 750's and the 2001+ ?

Another question that I have is, how do I check to see if the engine is stolen or not? It's easy to check the VIN# to see if the frame/bike is stolen or not. But most of the track bikes out there are built by individuals; therefore, I want to make sure that I don't buy any stolen stuff.

Thanks!