I'm working on an old Schwinn exercise bike. It dates back to the 1970's at least. It has an unusual thread pitch on the front wheel axle. It appears to be a 3/8-26 TPI with a rounded profile. After a little research it appears the British Standard Cycle (BSC) threads are 60 degree but with a rounded crest similar to the British Whitworth 55 degree threads.
Does anyone know if Schwinn did use this thread style? Better yet where can I find a tap?
Does anyone know if Schwinn did use this thread style? Better yet where can I find a tap?
Last edited: