Cycling did not appeal to the masses until the introduction of the pneumatic safety bicycle with a chain and sprocket drive (the prototype of the modern design).

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British engineer James Starley is, perhaps, most commonly associated with the iconic (and slightly ridiculous) Penny-farthing with its oversized front wheel, but the "safety bicycle, " which his nephew developed the first commercially successful version of in 1885, is the blueprint for most modern bikes.

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The shock absorbance numbers are impressive, says Randy Swart, director of the Bicycle Helmet Safety Institute in Arlington, Va.

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Randy Swart, director of the Bicycle Helmet Safety Institute in Arlington, Va.

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