The EdgeRider wheels provide stability and easy rolling at the same time, by combining three major design solutions:Shape: in different ways for each machine, but the wheels are either "wedged" between the edges of rails, or "grab" the rails to eliminate sideways play, thus holding the machine firmly on the tracks. Some Gammill customers report an unexpected side effect of the "wedging": less vibration.Material: the wheels are made of a high quality plastic, with an "oily feel" to its surface, which reduces abrasiveness, one of the causes of aluminum oxide buildup.Dual ball bearings: to reduce the unavoidable axial play (wobbling) of any single ball bearing, the EdgeRider wheels have two ball bearings. This feature increases the stability of the machines, and on machines with horizontal wheels reduces the strain on the individual bearings, and are practically equivalent with the use of more expensive thrust ball bearings.The EdgeRider wheels are manufactured by precision machinery, and each wheel is tested by spinning at 16,000 RPM. Each EdgeRider set comes with: 8 Precision Wheels Installation Instructions All Bolts/Nuts/Spacers needed for installation
