Originally Posted by
Russ Roth
There was a short period of time in which MTBs transitioned from older road dropout spacing to the more modern 135mm, but mostly on cheaper bikes from the late 80s/very early 90s that used freewheels. At this point you won't find a replacement for the two narrower spacings, I can recall having to stretch a couple of frames slightly when we could no longer buy MTB wheels in narrower spacing and had to make more modern wheels fit. Assuming 135 on a 90s GT MTB would be considered a safe bet.
This is a very solid answer. I would not have thought that our bikes were that old - one was my neighbor's daughter's bike when she was a teen. The other was from a priest at our church that left it behind a shed when he moved on. I have not tried the frame stretching route, but it sounds intriguing. I could probably get 70% of a centimeter bend out of a 35 year old steel bike with bar clamps. I've been going the wheel repair/rebuilding route instead, because hubs are readily available. The rims must be too, because you can still buy 26"/135mm wheels, I just haven't seen them.