1949 Cyclotandem Derny 98cc Zurcher engine

1949 Cyclotandem Derny 98cc Zurcher engine

This is the Derny tandem I sold in one of my BuyVintage auctions:


The Derny is 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.


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


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.


Motorized tandems are a uniquely French thing. A few vintage ones are now being rallied in Britain, though I’ve not yet seen anything as brilliantly ungainly as this Derny tandem.


The engine is a beast of a 98cc Zurcher.


The engine has good compression. It’s an excellent project that’s waiting for someone to restore it to its former glory.


I bought new tyres for it and fitted them (£50 the pair from Tony Etheridge). But we got side-tracked; I restored another French tandem, and I now have several other restorations on the go; so the Derny got put back into my storage, which is why I’m selling it.


This Derny is complete except for the chain-case on the off-side (see above).


But I bought another Derny tandem to use as spares, which has the chain-case needed. (See page 91 of this auction catalogue CLICK HERE).
The second Derny tandem will be in another of today’s auctions, and will finish after this one so that the successful buyer can buy it too if they wish: the second one has an incorrect engine and no petrol tank, so it should be cheap enough to buy for spares.


I’d like to see photos of the Derny tandem when it’s done.





The idea of the Derny was designed and constructed by two French ex-racing cyclists called 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. And 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.



I also advertised another Derny on the http://BuyVintage.co.uk website, this time my friend Peter’s 1949 Derny d’Entrainement Bordeaux-Paris 98cc Zurcher


This rare machine is one of the original Derny Cycle-racing pacers. You can see more details of the model below:

I have a Cyclotandem Derny for restoration, which is also in this 2nd BuyVintage auction. You can see it on page 43 of this website catalogue. The tandem and the pacer would make an excellent pair!


This rare Derny is owned by my pal Peter. He bought it from our mutual friend Richard, but neither of them have had it running. In fact, these pacers are quite hard to ride – so there’s a challenge for the successful bidder!

That is what we really like about cyclemotors: they are reminiscent of the earliest pioneer motorcycles. And the Derny, with its distinctive handlebar-mounted petrol tank and the sizeable Zurcher (98cc) engine between your legs, has the most primitive pioneering early-20th Century styling of them all.





Published on October 2, 2008 at 2:22 pm  Leave a Comment  

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