Science Projects And Inventions

Derailleur Gears

"He [Paul de Vivie] was a man who devoted a lifetime to the perfection of the bicycle..."
Clifford L. Graves, writer
Paul de Vivie (1853-1930) did not buy his first bicycle until he was twenty-eight, but his passion for cycling would eventually take over his life, and led to the invention of a new system of variable speed cycles.
De Vivie's first bike was an "ordinary" high-wheel, or penny-farthing as it's more commonly known. The pedals of this bike were attached directly to the wheels so that one turn of the pedals equaled one turn of the wheel. De Vivie sought a way to improve this ratio to make cycling more energy-efficient. In 1887, he set up a cycle shop in the mountainous region of Saint-Etienne, France, and launched a magazine, Le Cydiste, in which he wrote passionately about cycling, under the pen-name "Velocio."
De Vivie's first attempt at creating gears for a bicycle involved two concentric chain wheels with a chain that had to be lifted manually from one to the other. In 1905, he tested a two-speed derailleur gear, but the cycling world was reluctant to buy into the idea, dismissing it as an easy way out. To win over the skeptics, de Vivie organized a mountain race between a male cyclist on a single-speed bike and a female cyclist on a three-speed derailleur bike. Much to his delight, the woman won.
Today, modern bicycles frequently may have more than twenty different derailleur gears, making riding in even the most varied terrain a breeze. 


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