First thing. Does the frame have horizontal or vertical dropouts? They are located at the rear of the frame where the rear wheel is put in. If horizontal, you need a special hub probably requiring to be built or just flat out purchased already built. If vertical, you can get a flip-flop hub in which one side of the wheel has a freewheel, the other side is what track riders called fixed gear. Fixed gear is usually for REAL experienced riders. This means that as the rear wheel spins, the cranks spin, no matter what. NO FREE WHEELING AROUND. It is very difficult to stop if you ride a fixed gear. The rear spacing is usually 130mm. Look also to see if there are drilled holes to install brakes. Some of these frames, mostly true track frames, have NO holes drilled out. Make sure you go to a good bike shop. Just like car salesmen, if they see you don't know too much about bikes, they'll take you for a ride. Hope this helps.