Citroën GS Birotor. Unstable prodigy

Citroën GS Birotor. Unstable prodigy
ER Classics Desktop 2022

Rarely has a car flopped into oblivion so progressively.

Perhaps one of the most special Citroëns since ages, yet almost no one knows about its existence anymore. Just like Dries Roelvink, except for that special one. And the Citroën GS Birotor was never available in swimming trunks yellow, Dieu thanks. Brown metallic or beige, there were no more choices for the spacious 600 Citrofiles who ordered one between 1973 and 1975. More were built, such an 850 allegedly, but there was no storm at the dealer. Well for the regular GS, that sympathetic middle class sold well. The most important criticism of this popular one Citroën however, it concerned the motorization: seasoned journalists and customers in a hurry or in a hurry found the GS under-motorized. Citroën came up with an unstable solution.


From a collaboration of Citroën Comotor was created with NSU. Previously experimented Citroën already with a Wankel engine in the M35, a coupé similar to the Ami. From these Projects F and G, the French car manufacturer entered into a partnership with the experienced German wobbly technicians and built an engine factory in Sarre. Comotor subsequently developed a two-disc Wankel engine with a converted volume of just under 2 liters and a power of 107 hp at 6250 rpm. The lack of power of the Citroën GS was solved with this, but not the problems. They just started. The brainchild of Felix Wankel was promising: relatively much power with a compact construction and low weight, fewer rotating parts and a low-vibration running were undeniably good qualities. However, there were some disadvantages to this special engine principle here and there: it was not (yet) very reliable, inefficient, had high emissions and also used liters of oil. Remarkably enough especially symptoms that indicate the necessary revision of a tired block, but this power station was new ...


The generous oil consumption of the Citroën GS Birotor of one liter per thousand kilometers was up to that point. That also had an advantage: an oil change was not necessary. There was a special button on the dashboard of the Birotor to check the amount of oil in the block. Topping up was enough. Just like the fuel, but unfortunately that also had to be in large quantities. In itself a disadvantage, but at the time of the introduction of the Birotor the infamous oil crisis broke out and a car with a high consumption with good decency could no longer be justified. Exactly, just like Dries' oeuvre. But a much bigger downside to the Birotor was its price. A Citroën GS Birotor cost new then about the same as a fairly bare, but divine DS 20. That meant an extra cost of about 10.000 guilders compared to the most expensive Citroën GS, de Pallas. No cat piss. In terms of advanced technology, its hefty price was still justifiable, but the biggest drawback was its appearance: it still did not surpass the middle class. such a same Citroën GS also had the neighbor, but much cheaper, he moaned.


He could want that. The Citroën GS Birotor was fairly clear of a normal Citroën GS to distinguish. Most recognizable were the widened fenders and the wider steel rims with chrome hub caps. Still a lot cooler than all the 22 inch fairground yo-yos we have today. Under the skin there were many more adjustments; among other things on the subframes, exhaust, bottom and inner screens, but the neighbor did not see that. If he looked closely, he could see a revised dashboard with a choice of round clocks and a different center console, front seats with fixed headrests and gold-colored chevrons in the grill. His indifferent wife noticed at most the GS Birotor badges, that there were other decorative strips on the sides and the sills were provided with aluminum frames. flute.


The press, on the other hand, was particularly enthusiastic about the Citroën GS Birotor. Its performance and driving characteristics were praised everywhere, now that the slow GS housed much more oempf under the hood. They thought it looked more like a new model in GS packaging than a GS with a heavier engine. The public did not, and that soon spelled his downfall. People were simply not prepared to pay that much money for a GS. The birotor would probably have had a much better chance of success if it had been used in the then new CX. Now the special technology has faded into too flimsy packaging. Hardly anyone was willing to constantly explain that his brown burger box was in fact an intelligently built one sleeper used to be. It became a fiasco.


Citroën after this wry conclusion did everything to make this adventure immediately forgotten. Especially because the idiosyncratic car builders did not want to be responsible for the expensive maintenance and parts of the shaky prodigy over the years. All unsold copies were immediately destroyed and a generous trade-in proposal was made to the existing owners. Subsequently, these exchanged copies were permanently disabled by punching a hole in the engine housing. A little less meticulous and progressive than the way the technology had come about, but it worked flawlessly. It is estimated that about 250 copies still escaped that slaughter. The majority of these are in the home country, but about ten of these special GSs are also known to be known in our country. Coincidentally, as many as all Roelvink albums still in circulation.

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Also read:
- Citroën GS. State-of-the-art and non-competitive middle class
- Citroën GS Pallas. A beautiful day full of childhood memories
- Robert Opron. The Citroën years
- Citroën CX Prestige Henri Chapron (1976), La Grande Dame
- Citroën SM (Sport Maserati). The prestige car of Citroën. 


Give a reaction
  1. That 'conversion' to 2 liters requires a bit of explanation. The 2-disc rotor chambers had a combined volume of 1000cc, so 500cc per chamber. Because there were 3 combustions per revolution/per chamber, resulting in higher consumption but lower efficiency, it was not a factor of 3 but 2 volume. The engine has been (in) the basis for the NSUs, Citroën, Van-Veen OCR, Norton, but also in pleasure craft for propulsion, generator sets or even water pumps in agriculture.

  2. The sheet metal of a Citroen was the result of light construction. Weight costs energy and reduced agile handling. Top constructors often employed aircraft engineers. If you drive an Ami with 30 hp and you drive afterwards in a C5 with 140 hp, you naturally feel power and weight in the latter case, but in the first case light-footed and frisky. Those two AMI feelings are not wrong at all, I can assure you.

  3. It is remarkable in itself that Citroën has not become more involved with Wankel engines. The combination of hydraulic suspension and braking system, Diravi power steering and vibration-free, turbine-like Wankel engine would make the ideal Citroën have yielded.

  4. I see at least 6 more on a valid license plate, but not a single original Dutch license plate, all later imports:
    LL-03-HH, GY-68-ST, LF-24-RY, 28-YD-99, 65-YA-56 and YP-40-XN.

  5. I don't know how many there are in the Netherlands, but I do know that one of them is in the recently opened car museum of Henk Visscher in Buren. Right next to the Peugeot 504 convertible with which Ilja Gort has made his last wine trips.

    • I see at least 6 more on a valid license plate, but not a single original Dutch license plate, all later imports:
      LL-03-HH, GY-68-ST, LF-24-RY, 28-YD-99, 65-YA-56 and YP-40-XN.

  6. There is also a copy in the Netherlands that (according to the note from the owner, but that is how it looked) was originally delivered in blue metallic. He also drove a number of guests across the airport on the CitroClassica. Very special sound and it went like the fire brigade! Must have cost a few liters of oil I guess 😧

  7. I've always been crazy about most Citroëns, and to this day I still drive a CX Diesel.
    I've seen the GS Birotor, never driven it, but it just looked too rickety for what it had to cost. The sheet metal on a GS has never been tight. It was a great car to drive
    to drive. Still, the GS never looked expensive. It didn't matter how many Pallas strips were pasted on, you couldn't obscure the thin sheet metal. It's a bit like the Chrysler
    K-Cars. cheap, it screamed "Cheap" from afar. You could also buy it “diddled-up”.
    All the rococo glitter and chrome and vinyl roofs couldn't hide that the sheet metal was crying. What more or less killed the wobbly engine here was the sound that came from the exhaust. Mazda has lasted for a long time, but when Aircare was introduced, it turned their heads. Thanks for the special article. Very nicely written by the way.
    Hi. Photo is from yesterday

  8. Well, I didn't know him. What a special car! Must have driven very nicely. The only Wankel motorcycle experience I ever had was driving a Mazda MX-8. For me that was the most beautiful motorcycle character ever. He always did what I wanted with gas and he hung on the gas with a poisonous bite. Beautiful! If that GS also ran like that, then it must have been great. And yes, that vibration-free running. Addictive!

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