Originally Posted by
tricky
Why avoid the u-brake? They are a little more work, but if they come across a deal I don't think it should be a deal breaker. He might even be only running a front brake.
As I understand it people like to play around with rings/cogs for fixed gears. There's no upside to buying a frame with brake bosses down there; you run the risk of finding just the right ring/cog combo and then realizing the chain hits the u-brake boss. There's so many other old mountain bikes out there that won't have this issue, so when considering a fixed conversion it's best to simply avoid them if you can.