Originally Posted by
andrewclaus
You mentioned at first that you banged the bearing out with a bolt. Presumably that means you worked side-to-side. I recently heard that one can ruin the frame doing that. The new bearing may not press tightly into the shell.
I had a similar issue with a 19 mm FSA bearing. I made a "rocket tool" out of a piece of 1/2" EMT (conveniently 18 mm OD) and that worked fine. Luckily I heard/felt the bearing in the early stages of problems, cleaned and greased it, and it's working okay so far. I pressed it back in with threaded rod and an assortment of sockets and washers.
You can bang out bearings with a punch without too much worry of damaging the shell. But in OPs case, he has a BB whee the bearings are in cups which are then pressed into the frame shell. Those cups aren’t designed to have bearing banged in and out of them, they are designed to be replaced as a unit, so they could be damaged when replacing the bearings.