I just bought, what I have been told is, a 1930's track-bike frame.
The BB casing measures 66mm.
From what I've read this morning a 68mm BB should fit, so long as the threads in the bb casing are English...
...But I have no idea whether the threads are, english, italian or otherwise.
Anyone know how I would measure or perhaps what threads Master Sports is known to have used?
Have attached a picture for fun.