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sandranian · Site Admin

Here is more evidence that Gitane really "invented" the aerodynamic bicycle. Excerpt from Road Racing Technique & Training (1988) by Bernard Hinault and Claude Genzling (1988, Capital City Press, first published in 1986 in French as Cyclisme Sur Route, Robert Laffont S.A., Paris):

Pages 44-46
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Aerodynamics

The first studies on reducing the bicycle's aerodynamic drag and improving the aerodynamics of the man-machine unit through riding position were done in 1977 by Maurice Menard, director of the Institut Aerotechnique of Saint-Cyr-l'Ecole and professor of the National Conservancy for Arts and Trades. From this came the Profil bicycle tested during the 1979 Tour de France and later the Delta bicycle used by Laurent Fignon in the time trial stages of the 1984 Tour de France.

Bicycles with sloping frames, cowhorn bars, and smaller front wheels had already appeared in the Eastern bloc countries. First they were used in team time trials where the purpose of the smaller wheel was to improve drafting, on the same principle as a stayer bicycle. Then, when it was realized that they had less wind resistance, they were taken to the track for the pursuit and the kilometer.

It wasn't until Francesco Moser broke the world hour record in 1984 on a bicycle with a sloping frame and disk wheels that aerodynamic studies of cyclists were taken seriously. However, aside from the wheels Francesco Moser's bike was not an aerodynamic bicycle in the strict sense of the term. The innovatively shaped frame was built with traditional round tubing without a special profile. The reduction in drag came mostly from the disk wheels and from the Italian champion's very elongated position. With the exception of the Delta bicycle almost all special bicycles now used in time trials are directly derived from Francesco Moser's bicycle. Except for the wheels, this is still very close to the first sloping-frame bicycles of the Soviets. On the flat these bicycles save 2 to 3 seconds per kilometer when compared to traditional bicycles with traditional wheels, without profiled rims or flat spokes. It's difficult to determine exactly how much should be attributed to the inertia of lenticular or disk wheels.

The current trend of research is to continue in the direction shown at Saint-Cyr-l'Ecole in 1977. This was to reduce the drag of the bicycle itself through modifications in frame design and to create new components, such as the airplane-wing handlebars invented by Maurice Menard in 1980 which several manufacturers copy today.

What are the limits? With the Delta bicycle the power savings had reached approximately 120 of the 200 watts a traditional bicycle consumes in wind resistance.

Although they are not as aerodynamically refined, current Moser-style bicycles offer a comparable gain thanks to disk wheels.

It's reasonable to expect to gain another 50 watts with the new generation of aerodynamic bicycles that were presented at the Milan show in 1985.

Since a superchampion can produce approximately 600 watts in an hour, a gain of 170 watts over traditional bikes will easily put the hour record beyond 53 km at Mexico City altitudes and allow averages of 51 kph in time trials. That is if the rules, challenged once more, will allow such machines to be used.

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Gtane

Thanks for the info. Stephan, an interesting subject.

This is a tricky one to pin down as to who was the first, but as you say 'invented'. As an example of the Eastern European frames, Takhion were an early version of an aero machine with fork crown bar mounts using low profile bars but where they actually placed against Gitane, I just don't know.

An example of the Takhion;

http://tinyurl.com/yjgdksc

At this time (very late '70s to mid 1980s) a number of people were experimenting with frames on the time trial scene in the UK (no doubt other countries too) as they were with track bikes. Many UK frame builders tested ideas but pinning the builder down can be extremely hard as a number not only did not have the frame builder's name on but were not allowed to, particularly in the 1950s (although that might possibly be too far back), or didn't want them to be shown. Finding this info. now is tough. I often wish that I had kept all my cycling magazines.

By the way, 'Road Racing Technique & Training' is a great book.

Tim

sandranian · Site Admin

Not to play the contrarian, but that is not an "aero" machine. The eastern bloc countries developed "funny bikes" which were used to keep the rider in an aerodynamic position (and to improve drafting by moving the rider closer to the one in front of him by using a 650 front wheel)...not to improve the bike's aerodynamics.

Gitane was the first to build bikes which were tested in a wind tunnel to improve the air flow over the bicycle itself, not just to improve the rider's position on the bike. TT bikes have been around for a long time, but it was Gitane who started taking time off of TT's by improving the aerodynamics of the bicycle itself.

Gtane

Stephan,

I agree about the rider v the machine but in changing the position of the rider on the bicycle the bike is more likely to become more aerodynamic as a result of getting into a lower position while reducing the frontal areas of the bike to achieve less wind resistance. Whether or not more slippery tubing or technology is used.

Anyway, this is all splitting hairs and probably way away from the point. The ingenuity of Gitane and their tapered or wing cross sections, and the way they pushed the envelope of design and technology for time trials and the track was superb.

Thanks for getting the grey matter working again. Great post.

Tim

sandranian · Site Admin

I don't think we are splitting hairs...this is fun conversation in my book!

To further the talk, I would answer that an unintended improvement in bicycle aerodynamics (which I don't think has been proven with the smaller front end, but was shown with the 650 front wheel) does not qualify the bike as an "aero" machine. Again, the funny bikes of the early 1980s were done only to improve rider aerodynamics. The 650 wheel was shown to be more aero even on ITT's, but was originally conceived for team time trials/pursuit...again, to move the riders closer to one another.

I guess one can invent something by accident, but I guess as far as this topic is concerned, I am also looking at the intent of the designers.

Gtane

I'm glad that we're not splitting hairs. Great news.

I don't know whether the reduction in frontal area of these lower profile machines at this time came as a result of design or was simply because of rider position. I would guess that there must have been some thought, and indeed intention, as you're looking for (but again I'm guessing here), going into the design to reduce airflow even if the bicycles didn't have aerodynamic cross sections. But this is just speculation based on the evolution of how a design might come together and the possible considerations, discussions and thoughts of the designer / design team. The cross bar on the Eastern European machines is very low indeed, providing for frame strength but also providing for less frontal area, as well as a lower rider position as you have indicated. As a feature, the shift in mounting the bars on the fork crown is quite a move away from the traditional stem, not to mention a far shorter fork tube and the potential loss of structural integrity through this lower position. One wonders why the head tube did not then remain consistent with, say, a traditional track frame with the bars simply mounted on the fork crown. The move to lower the cross bar seems to have been a deliberate design change with intent but the debatable area is whether it was to just achieve a lower position or was it to achieve the lower position and reduce the frontal area of the bike. That I just don't know and is the nub of what we're after.

The smaller wheel is a notable detail together with, in some cases, reversed forks on the track. This was certainly a significant development within in this design genre.

Here's a very interesting article where Dave Moulton talks about building bikes in the UK with aero shaped tubes (which he modified from round section tubing) in 1978, as well as actual aero tubed (from Reynolds oval section tubing) bikes which he built for the US Team Time Trial squad in 1979. There is also a mention of Gitane.

http://tinyurl.com/ykbte99

Tim

Wisey

I have to agree with Sandman on this one. The Funny Bike had one key advantage in that the use of the smaller front wheel allowed the riders in a team pursuit to have a shorter combined length from lead rider to tail rider. Whether this produced any meaningful aerodynamic benefit is probably unlikely. The smaller front wheel is certainly more aerodynamic, but the increased rolling resistance practically cancels out that benefit. The most common misunderstanding about funny bikes relates to rider position. It is true that some riders set up their position with an extremely low stance, but the effect that this had was the same as it is today: If you go too low, you lose power. See the pic below. A correctly set up Funny bike position places the rider in the same position as when in the drop position on a normal bike.

It was the introduction of aero bars (by the 7-Eleven Team at the Tour de Trump '89- not by GL at the TdF in '89) that changed how we think about rider position. It is interesting to note that we still have the same issue today with most riders having their bars set too low and thus losing too much power. As far as I can remember, Chris Boardman is the only rider to have an extreme aero position and still produce full power. LeMond, Indurain, Armstrong all ride a little higher and produce more watts.

On another note regarding Gitane's development of aero bikes. Did anyone notice the TT bike that Cadel Evans used at the Tour last year? He was wanting to get lower (!!!) but he already had the shortes head tube possible and was using funny stems to get lower. His sponsor came up with a novel idea. Let's cut the front of the head tube out and attach the bars through the cut-out. How very original Confused

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plchin014

Back in those days (late 80's).
My wife's cousin (who worked for the government of France), had a Wind-Tunnel that was frequently being "Borrowed" by French Professional Cycling teams for doing this type of research.

She mentioned names like Lemond, Hinault.
She was not a cycling fan.

Oh how I wish I could have been there (fly on the wall).

sandranian · Site Admin

On Evans' bike, good eye, Wisey! That is truly a throwback design.

trim

just saw this on the french interweb and thought it could interest some of you :

http://www.leboncoin.fr/vi/101031604.htm?ca=18_s

Gtane

I thought this info. (link below) might be of interest regarding the timeline of aerodynamic machines. It refers to an aerodynamic machine by Assos from 1976 and is made from carbon fiber.

http://tinyurl.com/3ahwg2u

[As a slight aside, there's a photo within the article of part of the display at the museum with a title statement (hoping my translation is correct) saying that Assos was the first to make a carbon frame 30 years ago (assuming the display was put up in 2006 in that the date shown at the beginning of the display title is 1976). That particular statement would therefore be incorrect (according the The Custom Bicycle) because Gerald O'Donovan, Raleigh, produced a prototype carbon frame (not aerodynamic) for the Anaheim Aerospace Materials Convention in 1968. The tubes for his prototype were glued together. Reference for Gerald O'Donovan's frame can be found in the book The Custom Bicycle by Michael J. Kolin and Denise M. de la Rosa, page 88.]

A machine of further interest is this Bill Philbrook Aero Special with info. referring to 1970 (first link below). I cannot find any more detail on this machine at this stage other than these links so really need other references for a date.

http://tinyurl.com/6zru99t (photos at the foot of the page).

http://tinyurl.com/66wlvxw

Tim

Wisey

Assos were certainly pioneers in tech advancement from very early on. I think that one of the issues with various people claiming to be the "first" to produce a carbon frame is that back then there was no internet and no real way to get the word out on your new invention. The industry was dominated by the 'big boys' who were spending huge sums on marketing their products (lugged steel for the most part). The magazines of course are always at the behest of the advertising dollars from those big players. I don't think it is a stretch of the imagination that quite a number of people all looked at the properties of carbon fibre and applied it to bikes, it was obvious. Who was the first? Does it really matter? Gitane wasn't the first to play with aerodynamics, but they were the first to perfect the art to the limits of technology at the time. I think Trek can be credited with doing much the same thing with carbon with their OCLV design in the early 90's. 15 years later other builders were still playing catch up.

I'm not sure there is enough gitane content in that post, so I will include a pic I found recently. Very Happy

Gtane

The aerodynamic area is a fascinating one but it remains to be seen how much further it will go over time with the UCI imposing their regulations and restrictions on bicycle manufacturers for race machines in UCI races. Perhaps triathlon machines will take on the mantle for further development.

Nice shot of the Deltas spinning along.

Tim

sandranian · Site Admin

While we are on the subject, on Facebook, I asked Thierry Marie his opinion of the Delta. He just responded (finally!), with two words:

"heavy bike..."

Wisey

Not surprising, but very funny all the same. Laughing