How The Decauville Car Shaped Automobile History

The Decauville car is one of the most obscure makes in car history. It disappeared without a trace, back in 1909. But it was enormously influential on the most famous motor car make of all: the Rolls-Royce.

The Decauville company was well known for making light railways, but had diversified into making the new Motor Car. This had been invented by Karl Benz in 1888, and popularised by his wife Bertha Benz on her famous road trip of that year.

The Decauville Voiturelle

Decauville’s first Voiturelle was well received on the French market in 1898. The little car had a tiny single cylinder engine under the seat, and this motor was made by De Dion-Bouton, a partner French car manufacturer that Decauville had made 3,000 tricycle chassis for.

It had no roof, just a padded seat perched on top of a four wheel chassis. There was room for three occupants, it weighed just 425 lbs (192 kgs) and sold for 3,500 francs- about $17,000 today (source: wikipedia).

The Voiturelle had a kind of sliding-pillar independent front suspension – quite possibly the first in motor car history – but no suspension in the rear! And it was steered by a tiller, not a wheel. But this little car was a good beginning.

A 1898 Decauville waits to begin the London to Brighton Veteran Car Run

Then a new twin-cylinder 5hp Decauville was released towards the end of 1899, propelling the Decauville into a whole different market. It was designed by Decauville’s Ravenez and Cornilleau. Soon the engine power was increased to 10hp.

The Racing Decauville

The engine in the new car was now mounted at the front instead of under the seat, and was water-cooled instead of air-cooled. The two-cylinder engine of 765cc, with a bore of 80 and a stroke of 76mm drove the rear wheels through a Bozier gearbox with only two forward speeds and one reverse. And a wheel was fiited for steering instead of the tiller.

Now there was suspension at the rear, with semi-elliptic fore and aft leaf springs together with a transverse semi-elliptic spring, suspending the previous Voiturelle’s rear axle. And at the front, like the previous Voiturelle model there was a transverse leaf spring and sliding pillars.

The chassis was made of tubes and the rear axle design of the earlier Voiturelle was adopted. But the body looked different, with a round bonnet and a radiator on the dashboard! That must have helped with cold fingers.

It weighed twice as much as the earlier car, 992 lbs (450 kilos) and cost nearly double at 6,500 francs ($31,000 today). But it was a much better car, as racing events would soon go to show.

Decauville won first in class in the Paris to Amsterdam Race of 1898 over 969 miles, then an amazing 1-2-3 result in the Tour de France in 1899 over a demanding 1,450 miles, and first place in the Coupe des Voiturelles in the Paris-Rouen-Paris event in 1900. Decauville also took the Daily Mail prize in the 1900 English Thousand Miles Trial.

Careful design and precision engineering had paid off. Briefly, Decauville were considered the best car on the market (source:

A green painted Vintage car with an open driver's seat.
The Renault AG was inspired by the Decauville…and so was the Rolls-Royce

The Decauville gets an admirer…

Meanwhile, in England, Henry Royce was the rather shy engineer owner of Royce Ltd, a Manchester-based engineering company making dynamos and electrical gear.

The end of the Boer War had caused an economic downturn, and cheaper foreign-made dynamos appeared on the market using Royce patented designs without paying him any royalties. Sounds familiar today?

So Royce either had to make his own products more cheaply or diversify by making a new product. As a perfectionist, the first course would have been anathema to him, and at around the turn of the century, he saw clearly that the new Motor Car was the next big thing. And it would be ideal for his business: precision engineering.

Royce first bought a De Dion-Bouton car to examine and then looked for another make. The Continent was in the forefront of car manufacturing at that early stage, the French in particular.

So then, the story goes, Henry Royce bought a 1902 Decauville with a 10 hp two-cylindered engine. This was the model that had been so successful in races and reliability trials. But Royce thought the engine vibrated too much and this offended his perfectionist instincts.

He was dissatisfied with other aspects of the Decauville, so in typical Henry Royce fashion he dismantled it, inspected the parts, made improvements and then built his own motor car.

An aristocratic car salesman, the Honourable Charles Rolls was on the lookout for an engineering company that could build him a new make of British car. When Mr. Rolls met Mr. Royce in Manchester both men found the man they had been looking for.

Rolls had been hunting for a British-built replacement for the French-built cars he had been selling to his wealthy acquaintances, and Royce needed a buyer with connections to the rich and famous for his perfectly-made but expensive machines.

Rolls deplored the lack of quality British car manufacturers and was on the look-out for a suitable car. What he found at Royce’s was a revelation. Although he disliked two-cylindered engines and had been looking for a three-or-four-cylindered car the smooth running of the two-cylindered Royce convinced him that here was a machine he could sell under his own name.  

So goes the Rolls-Royce legend.

But if the Decauville was so bad why was there so much of the French car in the genes of the Royce car? The radiator looked so similar that when Charles Rolls saw the car for the first time he thought it was a product of the French factory. The rest of it looked much the same.

So was the Decauville the second-best car in the world?

Henry Royce’s approach had always been to “take the best and make it better”, which later became the central Rolls-Royce mantra. And so he had set about doing exactly that: copying what worked on the Decauville, improving what didn’t.

As Royce once said himself, inventors and pioneers rarely make any money, only those who take their ideas and make them work.

He was a modest man, who always described himself as a mechanic. But where another car maker would use just a rivet, Royce would use a tapered bolt and nut.

“In 1904 he had produced the first Royce car: this was before he met the late Hon. C.S. Rolls,” wrote his friend Frank Lord “The car was a 10 hp. two-cylinder, and was a revelation for its date, having properly lubricated joints to the drive shaft [instead of chains].

As he could not buy a satisfactory coil for the ignition, he designed one, fitting very large points of the purest platinum, which, although expensive in the first place, never seemed to want adjusting or cleaning. The coil itself was as nearly perfect as possible, thus from the very first making the car reliable in a part in which, with most cars, there was endless trouble.”

Frank Lord Henry Royce obituary, Autocar May 1933

When the two friends took the car out for an ambitious run in Wales, the famous Royce reliability shone through:

“During the whole three days’ trial we never had a stop of any sort from any fault of the car, a pretty good performance for a car designed by a man who had never designed one before; yet only what you could expect from one designed by Mr. Royce.”

Frank Lord op cit

Decauville – the legacy

On a personal note, my old school friend Trevor Ellis owns a Decauville Reg no. FP4 which was the first car registered in the county of Rutland with FPs1,2 and 3 being allocated to motorcycles for the post office. In 2022 it completed the London to Brighton Run and was awarded President’s choice at the Concours D’Elegance at St James Palace on Saturday prior to the run.

Rolls-Royce cars, built with Henry Royce’s painstaking precision soon became known as “The Best Car in the World”, but few knew or cared how much a little French car had contributed to their success.

The parent company stopped making cars in 1909, and so the Decauville disappeared into history.

But the little French car had inspired one of the most important collaborations in the history of the motor industry: Rolls. And Royce.

This blue Rolls-Royce Silver Ghost could thank the little Decauville car for inspiring Henry Royce
A 1924 Rolls-Royce Silver Ghost