Just a little home made tool made from piano wire with a short tapered end. I can usually get it into the little groove between the case and bearing then just give it a yank. Doesn't always work. It was something shown in a very old book on rebuilding OS four strokes I have. In this case tonight the engine was an OS .55 and the case was broken in a crash. My friend finally got tired of fixing it with JB weld and bought a new case. Before he went home it was decided to give it one last try. I used my small hand torch and heated the case on the outside at the bearing area and just below. One good wrap on my building board and the bearing just fell out. It took the torch, I usually just boil the engine in water and give the bearing a slight tug and they come out. This one was really in there. I really cooked the case, heating may be an understatement.