To reach 65 miles an hour, a bicycle rider has to pass through five varieties of breeze and four varieties of gale and enter what wind experts officially call ”storm.” Little wonder, then, that the future of cycling is converging with the future of aerodynamics.
This once-simple sport has become a laboratory for new technologies of streamlining–helmets like jet canopies, wheels without spokes, advanced composite materials–that are spilling over into other sports and even into aircraft research.
For the California cyclist who won $17,000 by breaking the 65-mile-an-hour barrier, and for the scientists and health experts who gathered recently in Colorado Springs to discuss the evolving science of cycling, this is as it should be.
Bicycles have the elemental appeal of moving across the earth`s surface at the greatest speed possible with only the energy of the human body.
In fact, bicycles are but one class of ”human-powered vehicles,” a growing category with its own international organization, competitions and technical literature. There are human-powered aircraft, offspring of the Gossamer Albatross, which crossed the English Channel in 1979, and human-powered hydrofoils capable of skimming past ordinary racing shells.
But bicycles are the fastest. The $17,000 Dupont Prize was offered in 1982 for the first human-powered vehicle to exceed 65 miles an hour.
Last May 11, a rider named Fred Markham hit 65.48 miles an hour on a
”flying 200 meter” course–he was allowed a flying start–at Mono Lake, Calif., in the thin air at 7,500 feet just east of the Sierra Nevada.
His bicycle, named Gold Rush, was designed by Gardner Martin of Watsonville, Calif., and it had all the features that now identify the ultimate cycling machine. The entire bicycle and rider were enclosed in a shell like the nose cone of a missile, with two slits at the base for the wheels.
Such innovations are largely forbidden in ordinary competition, but under pressure from the human-powered camp some restrictions were relaxed for the 1984 Olympics.
There is considerable ferment within official racing circles about whether to hold fast against aerodynamic improvements that will at first be available only to contestants and countries with plenty of money.
”Technological changes are always pushing at the rules and have been since any sport was invented,” said Chester Kyle, a founder of the International Human Powered Vehicle Association. ”You`ll see maybe 12-pound frames, composite technology replacing steel, technological advances in the design of tires. It`s continually evolving.”
In preparation for 1988, the U.S. Olympic Committee is studying new skintight clothing and other technologies for a variety of sports. Even for runners, Kyle`s research shows, a 2 percent reduction in drag means a difference of as much as 4 inches in the 100-meter dash and 30 yards in a marathon.
When a cyclist is going just 20 miles an hour, 90 percent of his energy is expended on wind resistance. That is why solid disk wheels are replacing spokes, which churn the air like an egg beater, and it explains the molded helmets that give the rider the look of a modern Mercury.
But weirder ideas are on the horizon. One key to cutting drag is keeping the airflow from turning turbulent. Some designers of human-powered vehicles, along with NASA researchers, are studying the possibility of using suction to keep air flowing smoothly along the surface.
”You have to have a porous skin–you use thin strips of material composed of porous plastic, or you drill holes in aluminum,” said David Gordon Wilson, professor of mechanical engineering at the Massachusetts Institute of Technology. ”A person might even be able to create the suction by breathing.”
