• Turning the races can help, especially if the pits are more pronounced on one side; as can changing the number of bearings: ie remove the cage and add another bearing.

    Either way, the principle is the same: to change the position of the bearings relative to the pits. The second method is more reliable, as the bearings and pits are now differently spaced, so they can't match up. It's pot luck whether you rotate the cups just enough or too much.