I don't actually have a bike with stripped bottom bracket threads.
What I do have is an 80's era Mavic 610, 1-piece, sealed, slip-in axle unit, and a 50's (?) Bayliss Wiley "1-piece", unsealed, axle unit. The B-W unit looks like a regular bottom bracket fit into a thin BB sleeve.
The Mavic's shell is 33.6 mm in diameter, obviously designed to slip into a standard bottom bracket shell which is typically 35 mm (1.37") in diameter on the inside.
The Bayliss Wiley shell/sleeve, on the other hand, is 36.4 mm in diameter. The cups look as it they are standard in every way. For it to work, the threads (and possibly the entire length) of the BB would need to be reamed out.
So, my question is, were such shells brazed to a freshly reamed out bottom bracket, and if so, what tool was used to ream out the BB shell, and how was it done?
Or was there some other way of using them?
How are badly stripped bottom brackets repaired nowadays?
YMHS,
Amir Avitzur
Ramat-Gan, Israel