Miguel Correa just posted up the beginning of a great series on Response in Unresponsive YoYos, a discussion on bearings. If you aren’t already subscribed to his site, Definitive YoYoing, you should be.
Your yo-yo of choice is about trade offs. Size, weight, and material are factors in a yoyo that you cannot change (generally speaking). Your choice of bearing, however, is a variable. There are many types of bearings; steel, spec, ceramic, center trac, concave, the list goes on. Those all have their own traits and marketing behind them, but what I want to focus on are physically different bearings, Flat vs. Curved.
Click through to read the rest: Response in Unresponsive YoYos Pt. 1