This rotor is the same as the .125 thick rotor mounted in a previous picture. Notice its center has been relieved .015 deep on both sides in order to keep it centered inside the dyno housing & also keep the .250 thick clamping hubs in the same position. By using pockets, rather than holes, & alternating pocket locations from side to side, (the reason for the two dowel pin locations) a total of 48 pockets can be machined in the rotor faces. With a .125 thick rotor mounted, the clearance from the rotor face to the housing inside face is .0312 in. With a .1562 thick rotor mounted, the clearance is .0156 in.
