Originally Posted by
grumpus
Hubs come in different widths (over-locknut dimension, OLD) and frames come in widths to match hubs; respacing a frame to match a different hub width can be non-trivial.
respacing can also open several cans of worms that slowly crawl out and bite people.
like when i tried to respace a donated old aluminum road frame, and ended up with an aluminum paper weight ... or a customer's old steel bike that had been spread more than enough, but hadn't had the dropouts reset, so the hub was binding and self-destructed, repeatedly.. and the wheel was crooked in the frame, causing some rather odd and dangerous handling...