Originally Posted by The Fixer
Watch those track crankarms clearing wide splayed chainstays...
Or, just use a mountain bike crankset. The outer chainring on MTB cranks is positioned at 52mm if you use the crank's matching BB. Hence the 'standard' 52mm spacing on MTB single speed and fixee hubs (Kogswell, Phil, Surly, On One, etc.). I'm no expert, but I've heard that MTB cranks are pretty easier to find. And the MTB single-speed craze has left us with plenty of nice rampless/pinless chainings that fit them.