1907 De Dion Type AU

Comte de Dion was shopping for toys to give as prizes for a ball he was planning when he stopped at the Giroux toy shop on Paris's Boulevard des Italiens in December 1881. It was there he saw a model steam engine that was very well built. Impressed with its craftsmanship, he asked who had built it and was directed out back to the workshop of Georges Bouton and Charles-Armand Trepardoux. For meager wages, they built steam engines, scientific instruments, and model boats. Recognizing talent, the wealthy entrepreneur Mr. De Dion asked these working-class craftsmen to build a full-size engine at a much higher wage.

In a run-down building on the Rue Pergolese, near Avenue de la Grande Armee, the center of Paris's bicycle industry, Bouton and Trepardoux began building steam-powered vehicles. The problem was the boilers were inefficient unless they were very large, which caused other problems. The pair began experimenting with a tricycle and then a Victoria quadricycle with rear-wheel steering in 1883. Among the issues facing these early prototypes were the liquid fuel which was prone to fire, and the large vertical boiler typically positioned at the front. A more compact design followed with conventional steering at the front wheels and power driving the rearing wheels via connecting rods. The sophisticated boiler required 'just' 45 minutes to steam and had shorter vertical boilers made from concentric rings. A tank under the seat housed the water and the coal resided in a square bunker surrounding the boiler. The dual engines beneath the floor powered close-set rear wheels through locomotive cranks. The compact design made it relatively light at just over 2,000 pounds. This vehicle was named 'La Marquise,' after the Count de Dion's mother and it participated in the first motor car race in 1887. No other vehicle showed up. From Paris to Versailles, the prototype quadricycle averaged 16 mph on the 20-mile journey and peaked at 37 mph on the straights.

By 1889, enthusiasts could purchase the tricycle for 2,800 francs and the quadricycle for 4400 francs. Approximately 30 examples of the De Dion steamers were made, including about 20 tricycles, a few larger carts and carriages, and four or five quadricycles.

Trepardoux favored steam power, so as gasoline-powered engines gained popularity by 1893, he left the firm and presumably returned to making toys. DeDion and Bouton primarily focused on gasoline-powered automobiles and patented their transmission in 1895. The engines they built powered many of the early marques, such as Pierce-Arrow, Delage, and Renault. An estimated 140 makes worldwide used De Dion engines, including the De Dion-Bouton Motorettte Company of Brooklyn which was founded in 1900. It acquired the De Dion license from Kenneth A. Skinner, controller of the French firm's patents in the United States, and marketed its vehicles as the 'American De Dion.' The company operated for approximately a year before Skinner revoked the company's license.

The early De Dions used a 'vis-a-vis' type seating arrangement with the engine positioned at the rear. The passengers sat facing the driver. The single-cylinder engine of 1900 had an 80mm bore and stroke, with a displacement size of 402cc, and produced 3.5 horsepower. As the technology evolved, the epicyclic transmission was replaced by a standard plate clutch and the engines gained mechanical inlet valves. Designs abandoned the 'French Front' alligator hood and adopted an above-frame radiator.

A 6 horsepower engine arrived in 1902, followed by an 8 horsepower engine in the Model K. By 1903, a two-cylinder engine was delivering 12 horsepower, and two years later, a four-cylinder engine brought output to 15 and 24 horsepower, depending on the configuration. The final single DeDion cylinder engine was built in 1908.

The De Dion-Bouton Type AU Two Seater

The Type AU was equipped with a 942cc, side-valve single-cylinder water-cooled model that used a single carburetor and offered 8 horsepower. It was paired with a three-speed manual transmission and stopping power was courtesy of rear mechanical drums and a transmission brake. The suspension was by semi-elliptic leaf springs.

by Daniel Vaughan | Apr 2022