The BB stands for Ball Bearing. Some of those suffixes tend to be manufacturer specific. For instance I have no idea what CU stands for. but LA is OS Max's suffix for a bushing motor, non ball bearing. The FX , such as a OS Max 46FX is a ball bearing motor. as is the AX made by OS Max. A bushing motor tends to have less overall hp. Its just my opinion but I believe it is because there is a greater friction or resistance to movement in a bushing motor than in a ball bearing motor. While the Bushing motors are lighter and less expensive, the ball bearing motors offer a better performance and higher top end(for the most part). Also the power curve, (the time it takes to obtain full hp versus the top hp) is steeper on a ball bearing than on a bushing,,,,resulting in a faster acceleration. Any one else wanna add onto this thread, let us know what some of the other mfgs suffixes stand for.