This new power-steering, mechanical-drive riding trowel has a powerful gas engine. The heavy-duty gearboxes and spiders combined with a torque convertor clutch provides a great weight-to-horsepower ratio for large and small contractors. The raised operator platform and hydraulic joystick positioning makes this one of the most ergonomically designed riding trowels on the market. The MSP 455 is powered by a 40 hp air cooled Kohler gasoline engine and has two 46-in. diameter, five-blade non-overlapping rotors. Allen Engineering Corp.