Hey Martin, I need a favor. Could you measure the O.D., I.D, and thickness of both your BST and OZ wheel replacement cush drives. I'm looking for an alternative to the absolute crap originally supplied with my Carrozerria race wheels. A set of theirs lasts about 8 sprint races and are shot. I have a machine shop at my disposal, so if either are close I can modify to fit. I tried casting my own polyurethane bushings....didn't work as well as I'd have liked. Any help would be much appreciated.