The caliper is hung on the axle and the torque arm bolts to the frame, so the caliper pivots on the axle with the swingarm moves. Usually the torque arm is mounted directly to the swing-arm so it doesn't have to pivot, which is what i think I will do. easier to weld a mount than machine a bunch of parts. I still cant figure out why they would design it like this. Perhaps is a suspension loading thing.