[huhhhhh]

I can confirm that my lug nuts are tapered and that is what's locating the wheel on the axle. Until I can pull a tire off and look at the center hole I won't know if the center hole is machined or just a cast hole. If it's machined it should be concentric to the lug holes thus making no difference if the tire shop uses lug nuts or the standard center nut on their balancing machine. If the center hole is cast then I agree that only lug nuts should be used by the tire shop to balance. I wouldn't think a cast center hole would be very concentric to the lug holes.

Maybe a call to the rim manufacture will shed some light on the center hole being concentric to lug holes or not.