I have a headset bearing that’s come apart. It’s a pretty standard cartridge bearing eg inner and outer races, bearings and a plastic cage plus two rubber seals. It came apart trying to remove it from a frame.

Any suggestions on how to put it back together?

They can usually be pressed back together in a vice, it’s not ideal, but you’ve got nothing to lose by trying(Did it to my King many years ago, and it’s still running perfectly smoothly).

Yeah that’s my last resort. At the moment though the problem is that the outer race is still stuck in the frame!

Any other takers?