NUMBER 02 - Haas Automation, Inc.

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The Derailleur
and the G-Boxx
The derailleur is a device used on chain-driven bicycles to allow gear changes – rather like the transmission effects
gear changes on an automobile. The concept dates back to 1905, when touring cyclists used primitive derailleurs
where the jockey wheel was brazed to the chainstay. Often disallowed in road racing in those days, derailleurs required
freewheeling, which gave their users a considerable advantage over fixed wheel riders who had to contend with peddle
scrape in turns.
This changed in 1938, when Simplex introduced a revolutionary derailleur having a jockey wheel capable of moving
in and out to effect gear changes, while also moving forward and backward according to the size of the sprocket.
Simplex’s design incorporated a cage similar to those still in use on some derailleurs to take up slack in the chain.
However, the Simplex system had a serious weakness: it was very sensitive to dirt and debris, and required frequent
cleaning and lubrication. Despite this, it was so successful that it was immediately allowed in the Tour de France, and
dominated racing through World War II.
After the War, Tullio Campagnolo invented the parallelogram front and rear derailleurs, which revolutionized
cycling in the post-War decades. Campagnolo’s parallelogram system was fast and more reliable than the Simplex
design, and the cable-operated front derailleur was a dream compared to previous systems. “Campy equipped”
became the motto for professionals and serious amateurs the world over. Later modified by Suntour, the basic
Campy design remains in wide use today.
However, the last couple of decades have brought tremendous change to the biking world, including the
emergence of competitive mountain biking. This relatively new sport – accompanied by significant advances in
bicycle frame design, construction materials and suspension technology – has brought many new challenges
to bike riders, designers and manufacturers. For example, when you’re hurtling down a rocky mountain pass at
anything up to 80 kph, the last thing you really want is a vital and fragile derailleur dangling from the rear of the
frame, vulnerable to damage from rocks or a spill. So in 1999, Karlheinz Nicolai set out to find an alternative
solution to the exposed derailleur.