Bikes Made For The Space Age

They've still got two wheels and pedals, but today's hottest bicycles owe almost everything to the Space Age--and look like they could zip along at warp speed. Borrowing freely from the aerospace industry, manufacturers are making bikes from fiber composites, metal-ceramic mixes, and molded plastics shaped into wind-cheating frames and parts. The new materials make bikes lighter and let them go faster with less effort than before. Also, new on-board electronics can do everything from change gears to adjust shock absorbers for the road conditions.

A design revolution has been under way since about 1990, when graphite bikes began showing up at triathlons, often at the winner's podium. The bikes, made of carbon fiber saturated with resin, were strong and light, but also expensive: $4,000 and up. Today, however, an entry-level graphite road bike such as the Trek 2100 can be had for $1,000, the cost of a midline mountain bike.

Prices were high, in part, because of carbon fiber's tendency to break apart and potentially injure cyclists, leaving manufacturers exposed to expensive liability suits. But computer design systems capable of predicting failures have resulted in more durable bikes.

NO TRIANGLES. Being able to mold carbon fiber freed designers from the "double triangle" construction of steel and aluminum bikes. What resulted were radical new designs to lower wind drag, including V-shaped bikes from Zipp Speed Weaponry that eliminated the tubes behind the seat. An aerodynamic design with blade-shaped tubes built by GT Bicycles for the U.S. Olympic team was so effective that the governing body of international bike racing is outlawing some aero models for offering an unfair advantage. That hasn't stopped Trek from releasing seven Y-shaped graphite bikes for road and trail use.

Carbon fiber and inexpensive molded thermoplastics also are going into parts. Seat posts, handlebars, pedals, cranks, and gear shifters are being made from such composites, as are aerodynamic wheels with a few thick spokes or no spokes at all.

Riders with a taste for ordinary-looking bikes don't have to settle for ordinary metal frames. Bikes made of titanium, once known as "unobtainium" because of its high price, are down from the stratosphere. A fully equipped titanium road bike costs as little as $2,000, less than the price of a stripped frame a few years ago. Titanium models are lighter, absorb shocks better, and are more durable than steel or aluminum bikes. Titanium frames also don't weaken easily from flexing and retain their shapes.

Bikemakers have borrowed high-tech production methods from the aerospace industry. Cannondale uses computer-controlled lasers to precision-cut tubes, making frames easier to assemble and less costly.

Electronics also are changing how bikes operate. Shimano, the world's largest bicycle-parts manufacturer, will bring its automatic transmission to the U.S. this fall. Called the Auto-D, it senses a bike's speed and how fast the rider is pedaling, then changes the gear. Bikes with the Auto-D shifter will start at $450. Shimano also has introduced the $70 Flight Deck computer, which indicates not only speed and cadence, but which gears are in use, among other things. And K2 makes a computer-controlled shock absorber called the Smart Shock. It reads trail conditions and adjusts the shock so the ride is softer on big bumps but stiffer on washboard surfaces, to provide control.

The shocks come only on K2 bikes and cost $180 apiece. All this Space Age technology won't turn weekend cyclists into Olympians, but it might make them feel like they are.

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