From 1926 Bugatti produced the Royale car model, which was a superlative with 300 hp, but could only be sold four times due to the global economic crisis. A new application was found for the engines that had already been produced by installing them in a new type of high-speed railcar. Bugatti called this vehicle “Wagon Rapide” or “WR” for short. The original design called “Présidentiel” was a streamlined railcar that was also used by the President. It stood on two four-axle bogies whose wheels were covered with rubber. In the middle were four engines that had been derated to 200 hp. The power transmission for each engine was carried out individually via a hydraulic transmission and a long cardan shaft to one axle each. The driver's cab was located directly above the engines in an elevated position so that the driver could see the track in both directions from his cupola.
In order to reduce the enormous fuel consumption, the WL (Wagon Léger) model was developed with only two engines and two powered axles per engine. There were also two- and three-car variants, in which the driver's cab and four engines were in one car. Since the three-car variant achieved a poorer power-to-weight ratio, a reduction gear for each engine was installed for starting. Because the assembled models had poorer visibility from the driver's cupola to the far end, an additional auxiliary cab was fitted at each end for maneuvering. Later the possibility was created to couple trailers. Some of these came from orders already placed for power cars that were modified before production. Since the two-engine variant did not have enough power to pull trailers, the “Allongé” (extended) variant with a length of 21 m instead of 19.30 m and later the “Surallongé”, which was now 25.38 m long, were created. This increased the number of seats from 44 to 52 to 73.
172 km/h were already reached during the first test drives. This was later improved to 196 km/h, while longer distances were scheduled to run at an average speed of 116 km/h. Customers included the État state railway, the Paris-Lyon-Méditerranée (PLM) and the Alsace-Lorraine (AL) railway administration. Nine Présidentiel, 39 two-engine, three two-car, seven three-car and five trailers were built. Since the vehicles had to be fueled with a mixture of petrol, benzene and alcohol and used a lot of it, the two- and three-car vehicles were phased out as early as 1952. Another cost factor were the drum brakes, which wore out very quickly. The 13 short two-engine vehicles were converted to trailers in 1945 and then used together with the other single-car vehicles. These were phased out by 1958 and today only the example of the Présidentiel, which was used by President Albert Lebrun, exists.