Petrol engine track car Dm 1/2 Rhaetian Railway RhB 1920 The muscle power needed for the hand-operated track cars was arduous and only produced speeds of up to 20 km/h. In 1920, the Asper company offered track cars driven by internal-combustion motors that were able to run at speeds of up to 55 km/h. The Rhaetian Railways bought one for its inspection journeys. The 2-cylinder petrol engine developed 30 times the power of the two men who operated the so-called pump car. The power was transmitted by means of a chain drive, as on a bicycle. Asper 0.55 t 7.6 kW 2-cylinder petrol engine 55 km/h 4 seats gauge 1000 mm restored by CFF in operation 1920-1960