bigbowlcut Thank you. The fixed-gear experiment survived the first summer and it's in the basement for maintenance. I used an old chain that was still in spec. and managed to squeeze the last miles out of it. So this spring, a new chain is in order.

JohnDThompson Oh, I'm keeping both brakes. I'm too old to try to impress. And thanks for verifying the received wisdom of the internet. It is possible to use a lock ring with an appropriately "vintage" fixed gear cog on a road bike; just not with the limited parts in my bin. Other than the risk of "unthreading" the cog from the hub, is there any other reason not to use your legs for slowing down/ stopping? Does changing the direction of the torque applied by the chain lead to a faster fatigue of the hub? I've seen freewheel hubs crack on the shoulder between the threads and the spoke flange.

79pmooney Hear, hear on the re-purposing of older road bikes for fixed-gear/ single-speed (or just riding 'em in general). Paradoxically and presently, my fixed gear ride is the only frame I have with an integrated derailleur hanger and my only bike without a rear derailleur. The 70's Fuji S-10s that I have possess forged horizontal dropouts without derailleur hangars (no modifications required). Now, if I could just find one locally in my size (25" frame).

cheers.