Our team, in between competitions, simply fabircated our own custom 9" wheels out of 1" thick aluminum stock. All the weight is now on the edge, and they have a custom chamfer now. Those turned out really nice
We love them now.
However, before we did this, we were using the 8" rubber tread wheels from the KOP a few years ago. What we did to somewhat improve consistancy was chamfering them, albeit rather crudely. The quickest way to chamfer them would probably be just spin them up and hold a file to them. (And cover anything below them!
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