In general I don't think press-fit bearings are intended to be removable from the cups. Especially the plastic cups it's easier just to replace the whole thing. I just put in the WM threaded AC bearing PF30 BB in my bike (Al BB shell in a carbon bike). I only have a couple hundred miles on it without any problem, but probably too soon to tell. Per WM instructions, I used grease on the cup/shell interface.

I did see a tool to remove PF bearings from the cups and it seemed very elegant but cost around $100.

scott s.
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