The White Industries Eccentric ENO is the simple clean answer to ones vertical drop out chain tensioning dilemma on a single cog bike. Flip/flop polished hub shell with fixed threads on one side and freewheel on the other. The hub fits into the drops in an offset position and can be rotated up and back thereby tensioning the chain. Once the chain is tensioned, securely fasten the bolts and you have ENO'd your ride. Sweet!
Had a wheel built up by Excel Sports with this hub to turn a road frame into a fixed gear for training and around town. Wheel turned out great and this hub is fantastic. Very easy to change chain tension and no problems so far with dropped chain or loss of tension. Splined on one side for White Industry sprockets and threaded on the other for a normal sprocket or freewheel. Looks great too
Pros: turns road frame into fixed or single speed easily
Cons: non so far