This is my 1996 Trek 8000zx frame and the water bottled holder screw wont unscrew. I guess the title is misleading - the screw just spinning and won't come out. I think the welding of the underlying nut is broken... so anyway, what can I do with it?
Prise up from underneath the bolt head with a flat blade screwdriver and unscrew. Worked for me on a Zaskar frame.
Most bike shops should be able to get it out and fit a new rivnut.
There's loads of options to try if you Google.
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