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Classic Derailleurs: Campagnolo Evolution

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No derailleurs capture the spirit of the classic era more than the Campagnolo's derailleurs from the 1950s through the 80s. Beginning with the Gran Sport in 1949, through the original Record, then Nuovo Record and Super Record, and even the C-Record of the 1980s, Campy's derailleurs evolved in small ways over the years, but never strayed far from their original design. They stood the test of time, and were widely copied.

Tullio Campagnolo, with a bike equipped
with one of his 1940s Corsa derailleurs.
Cambio Corsa derailleur.
Campagnolo's previous derailleur system, originally developed in the mid-1930s, was the rod activated Cambio Corsa model -- which had a pretty narrow gear range and was cumbersome to use. These early derailleurs used no pulleys, because racers of the time were convinced (mistakenly) that pulleys would add too much drag. To shift gears, the rider reached down low and behind himself to work the levers mounted on the seat-stay. The rider moved one lever to open the rear wheel quick release, then backpedaled while turning the second lever which operated a "fork" that moved the chain from one cog to another. The wheel moved forward or backward in the dropouts to adjust chain tension. Then the first lever was used again to close the quick release and to lock the wheel in place. A later variation, called the Paris-Roubaix, performed the same basic functions but with only one lever instead of two. To see one of the Cambio Corsa derailleur systems in operation, see here: (YouTube --this guy actually makes it look easy!).
The Simplex derailleur was state of
art in the late 40s.

In 1949, Italian racing legend Fausto Coppi famously won the Tour de France using Simplex derailleurs (Simplex had paid him to switch), which was probably something of a slap in the face to Tullio Campagnolo. The Simplex was a cable operated plunger-type derailleur that was considerably easier to use than Campagnolo's rod-operated designs. Many other top racers also were using Simplex, but ultimately the "defections" told Campagnolo that he had to do something big to reestablish his company at the top among racers of the day. The result was the Gran Sport.

The prototype Gran Sport, with dual-cable
operation. Production versions would utilize
a return spring with a single cable.
The Gran Sport, first introduced at a Milan trade show in 1949, used an articulating parallelogram design, as opposed to the push-rod or plunger action, to move the pulley cage in and out. That first prototype shown used dual cables to move the unit back and forth, but production versions used a single cable plus a return spring. The design was refined further over the first couple of years until a "definitive" version was finalized by 1953. With only minor changes, that Gran Sport design was the basis for almost all of Campagnolo's better derailleurs, as well as much of their competition, until the "index shifting" era.

The definitive Gran Sport, early 1950s.
The original 1963 Record.
A short-lived model.
The Gran Sport was made right up into the 1960s, but a slightly improved model was introduced in 1963 called the Record. Made of chrome-plated bronze and steel, the Record didn't look much different from the Gran Sport at first glance. The biggest difference was that the pulley cage pivot was moved slightly forward and upward in relation to the jockey pulley. This change improved the capacity and overall performance as compared to the Gran Sport. This Record derailleur was the top of the line for the next few years, but its time in production was very short overall, especially considering the longevity of other models.

An early 80s Nuovo Record from my collection.
The next refinement came in 1967 with the introduction of the Nuovo Record, made from cold-forged aluminum. The new derailleur was lighter, and it was a much more refined product cosmetically, too. The old Gran Sport and chrome-plated bronze Record looked almost crude by comparison. The Nuovo Record is the true classic among Campy's derailleurs: tough, reliable, and beautiful. That model derailleur would continue to be made, virtually without changes, until the early-to-mid 1980s. Such longevity in any bicycle component is really hard to imagine in today's market, where every year new "upgrades" make last year's components "obsolete" and any design more than a couple of years old is described as "tired" or "long-in-the-tooth."

Second-generation Super Record.
(wikimedia commons)
The original Super Record
was basically the same as
a Nuovo Record with some
titanium bolts and a black
anodized body.
In 1975, Campagnolo introduced the Super Record group. The original Super Record rear derailleur was almost identical to the Nuovo Record except for the use of titanium for the pivot bolts, and some black anodizing on the body. It was revised further by the end of the decade to include a smooth, non-textured face plate with a screened-on logo, and a slightly different pulley cage that I believe actually increased the capacity slightly over the Nuovo Record. Both derailleurs were manufactured and sold side-by-side until around 1984 or so.

In the mid 1980s, Campagnolo made a significant design revision with the introduction of the C-Record model. The basic parallelogram architecture was still based on the old Gran Sport of the 1950s, but the shifting performance was improved somewhat by adding a spring to the upper body pivot -- something that Simplex had done for decades. The styling was smoothed dramatically, giving it a modern aerodynamic look. Visually, it was attractive, but ultimately in performance it could no longer hold its own against the competition coming from Japan.

Mid 80s C-Record. Modern yet
old fashioned at the same time.
(campagnolo.wikispaces)
As influential as it was, there were definite shortcomings in the old drop-parallelogram design of the Campagnolo derailleurs from the 50s through 80s. For one thing, they tended to need a bit of finesse to get from one cog to the next -- the usual technique was to overshift a bit, then back off to get the chain onto the desired cog. The necessity for this "overshift/back-off" technique was exacerbated as one moved outward on the freewheel to smaller cogs because the chain gap between the cogs and the jockey pulley would increase -- the movement of the parallelogram simply did not allow for a consistently close chain gap needed for quick shifting across the whole freewheel cluster. In my own experience, making the shift to the outermost cog can be particularly troublesome and can require some serious finagling. Being able to shift under any kind of pedal load was also unlikely. These shortcomings were easy to overlook in the era of friction-only shifting. The technique needed for shifting was just a skill one acquired until it became automatic. Sure, Japanese derailleurs from SunTour in the 70s and 80s shifted better, but Campy had "mystique,""tradition," and legendary long-term durability. One often heard clichés like "Campy wears in, the competition wears out." Then again, one also heard, "Campy derailleurs shift badly, forever."

1988 Chorus -- scanned from a Campy catalog.
Slant parallelogram, with a "twist."
By the end of the 1980s, just like forty years earlier, it was pretty clear that something big had to be done with Campagnolo's derailleur design. The old drop parallelogram architecture that was introduced on the prototype Gran Sport in 1949 just would not work as well as the slant parallelogram design first created by SunTour in the 1960s, and adapted by Shimano in the early 80s as part of the first truly successful indexing system. Campagnolo tried to make their traditional derailleurs work with indexed shifting, but the weaknesses of the old design just wouldn't allow it to work reliably in that mode. In 1987 - '88, the Chorus was Campy's first attempt at a slant parallelogram (with an interesting "twist" -- literally -- that allowed the angle of the parallelogram to change). In 1991, Campagnolo finally introduced the first major overhaul in their derailleur design, fully copying the "Japanese" designs with slant parallelograms and double spring-loaded pivots. That is now the basis for all derailleur systems today, regardless of brand or country of origin.

Coming up in the next post: Copies and Competition. Stay Tuned!

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