1952 Cyclotandem Derny (98cc Zurcher Engine)



The Motorised Tandem is unique to France.

In 1936, France’s new socialist government ordained that the French people could have an annual national holiday. An industry promptly grew up around summer vacations, and bicycle tandems became popular. Some manufacturers started to make motorized versions to cash in on the tandem craze – a much faster way for a cycling partnership to get down to the south coast – but production was interrupted by the war.

Production resumed post-war. But by 1953 or so, scooters had become the new chic two-wheeler and ‘old-fashioned’ motorized tandems soon became obsolete. After all, they had no real advantage over a motorcycle, apart from being pedal start so they could escape vehicle tax and the need for a license.

Of course, half a century later we adore ungainly white elephants such as this …and the Derny Tandem is such a classic example of 1930s French motorcycle excess that it is admired wherever you ride it.




Derny_Tandem (22)


1952 Cyclotandem Derny

98cc Zurcher engine

(Now sold)



This wonderful contraption is in running order. You can see a video of my friend Alain riding it around his garden in the video below.

It is not UK registered, but has a French ‘Carte Grise’ registration document.

This Cyclotandem was in storage for many years. Alain nevertheless started it easily, although the petrol in it is stale. Before putting it on the road I would recommend flushing the tank and carb and putting in new two-stroke petrol (as we traditioanlly do whenever a two-stroke has been off the road for more than a few months).









derny tandem running






The Derny is very famous in France. Its design has hardly changed from that of the earliest motorcycles – essentially a bicycle with an engine attached. It’s front-mounted petrol tank is particularly distinctive. The solo Derny was used for cycle pacing, and its design did not change throughout its production.

Its fame is as a result of solo Dernys being used as pacers in cycle racing. In fact, the word ‘derny’ has become a generic term for motorized pacers.

The idea of the Derny was designed and constructed by two French ex-racing cyclists under the name Roger Derny and Sons. This was the conventional ‘motos de stayer’ (in the UK, ‘Big Motors’ is the term used today). These type of pacing machines used first for the Bordeaux-Paris were not very reliable for road use. So another type of pacing machine had to be designed. As a result the Derny was born and put into production in 1938.

The Derny brothers’ first factory was at 81, Avenue St. Mande and later they moved to Avenue du General Bizot, both in the French capital. When the parent factory closed in 1956, Derny machines for the Bordeaux-Paris were maintained and rebuilt by Service Derny of 88, Rue Picpus, Paris until 1974. Derny carried on making other types of machines but closed in 1958.


Later on, another type of Derny was re-introduced called a ‘Burdin.’ This machine had many problems: the mobylette engine and the frame were not strong enough for the job. Many manufacturers have tried to change the design over the years but have gone back to the original design because it is still as good today as it was way back in 1938. Pacers today are still called Derny – a fitting tribute to the Derny brothers who first thought the idea up in the first place.

Dernys today are made by Arie Simon. He used to make them in Holland, but has now moved his business to Neepelt, Belgium. The Siemon Dernys are used on the road, 6-Days and Keirins by all the pacers on the continent and the UK. They are made of the highest quality.











derny tandem