I was wondering if anyone knew why a fixie has to be single speed? Also why you can only have gears on a freewheel bike?
This is true. I remember the freewheel seizing up on my crappy Tensor 5-speed years ago. I was some distance from home, had to keep those pedals turning and also had to keep tension on the chain which meant having to use the brake to control speed a lot of the time (no leg-braking with that setup, the mech starts trying to take up the slack, then it all goes to shoot)Fixed gear and derailleurs just don't work because of mechanical reasons.