Originally Posted by well biked
....if you find that it has caged bearings, you can repack it with loose balls and it should solve the problem for awhile.
You have to understand this will require more loose balls than the number in the retainers, usually several more per race. The reason loose balls temporarily fix the headset is that, since there are more of them, they no longer line up with dimples in the races so they don't "index".