Originally Posted by
auxym
....I found out my rear axle and skewer are bent
And they were brand new a week ago! Ridden something like 30 km. Off to the lbs to get new ones, but what could have caused this?
Originally Posted by
auxym
It's set up ghetto-single speed right now, with a 48T biopace ring in the middle position and the 17T cog on the cassette getting an almost-perfect chainline. The tension is sufficient, no chain slap.
I haven't seen the bike, so can't speak with authority, but I suspect that you're on more on the long list of victims of running a single speed set up with a tight chain. Whenever I hear a single speed owner claim that he made sure that "the tension is sufficient" I'm willing to bet a few beers that it's excessive. Single speed chains cannot have tension, they must be slack at all times. Not very slack, but slack none the less. The rule of thumb is about 1/8-1/4" sag in the lower loop.
A tight chain is the surest, fastest way to bend the axle as the rigid chain pulls the sprocket forward.