the air-cooled four-cylinder engine was installed transversely across the motorcycle chassis, predating the bestselling fours from honda and kawasaki. the heart of the mv agusta four-cylinder is the crankcase rack. the crankshaft, cylinder and cylinder head were mounted on it. the rack took the nine-piece crankshaft in six bearing blocks, as well as the spur gears in the control tower for the double camshaft drive. after loosening twelve nuts, the units mounted on the rack could be lifted out. particularly striking was the fine ribbing of the cooling fins on the sump and the oversized cylinder head housing the double camshaft drive. the transversely mounted cassette transmission was driven by the engine through helical gears. it was connected to the shaft drive to the rear wheel via a spiral bevel gear angle drive.