Get high quality steel shell aluminum bearings. We use King Bearings. heat treated they look blued. The locks are stronger and they don't squash the centers out as easy from timing being advanced to far or High boost up to 60 psi. I'll bet they are loose in the rod. I have seen bearings you can spread with your fingers or when stepped on. A good bearing will go through a rubber sole of a shoe. Junk bearing you will flatten out.