If your using olympic size weight plates, this Z8 Smith machine gets a 5-star rating. We purchased this as it was advertised to hold standard 1" plates, which is what we currently own. The pully system can hold the 1" plates, but not the Smith bar. The diameter of the Smith bar was measured at 27.7 mm (needs to be 25.4 mm to fit 1" plates). Everything else about this Z8 machine was excellent. Very sturdy, easy to put together, well packaged, excellent value. We did need to add a tiny amoun...