Black Bruin motors with standard and special-made rim attachments, built-in brakes, and small size are available in sizes from 125 to 12,600 cc, and run smoothly at close to 0 rpm. Radial piston design provides high starting torque in low-speed conditions. Cam curve design provides precise balance for constant ripple-free output torque. Rotating housing design allows freewheeling to 1200 rpm without hydraulic power. Integrated freewheeling valve ensures on-the-go shifting.