The bicycle, one of the world’s most resolutely human-powered machines, will join the long list of devices that have switched from the manual to the electronic when a new gear system makes its debut this weekend at the Tour of California.
Although the battery-powered derailleur by Shimano promises to bring ease and accuracy to changing gears by enabling riders to shift with a light touch to two electronic switches, traditionalists worry that it may erode the basic tenets of the sport.
“People choose bicycles precisely because a bicycle’s motion requires only human effort, and nothing could be more simple, independent and autonomous,” Raymond Henry, a cycling historian in St. Etienne, France, wrote in an e-mail message. “Any source of external energy, however weak, runs counter to this philosophy.”
Whether the gear system becomes the next iPod and redefines bicycle technology or ends up as the sport’s version of the eight-track tape will hinge on a number of factors, the most obvious being performance, reliability and cost.
Two earlier attempts at electronic gear changing by a French company, Mavic, often malfunctioned in rain. Another company, Campagnolo, has delayed bringing its version to market because of the economic downturn.
Shimano’s version, known as the Dura-Ace Di2 7970, is being used by three professional teams competing in California: Columbia High Road, Garmin Slipstream and Rabobank. About 10 riders will race with the system even though they have used it on only one or two training rides after receiving them late this week.
Bob Stapleton, the owner and general manager of Columbia, said many of his riders had doubts about using bicycles that could literally run out of power. The Di2 system has no manual override if its battery goes dead. That event can be an irritation or a disaster, depending on the terrain and what gear ratio the bike is stuck in. Shimano estimates the battery will last for about 1,000 miles per charge.
“Their careers can be made on the results from one race,” Stapleton said of his riders. “So they prize reliability over everything.”
Stapleton, an experienced amateur cyclist, has used the Di2 system extensively and is a convert.
“I think every high-end bike within three years will have this, maybe sooner,” he said, adding that the system also eliminates much of the maintenance required by mechanical systems.
A full set of components with electronic gears will cost about $1,250 more than the newest mechanical version, which sells for about $2,750. Upgrading an existing Shimano system is expected to cost about $2,200. The system will fit onto nearly all racing bicycles.
Later this year, Giant, the largest bicycle manufacturer in the world, will offer a bike designed to use only electronic parts for about $14,000, which includes the cost of Di2. If consumers fancy the device, it will likely follow the pattern of other new electronics and drop significantly in price over time.
Electronic gear-shifting technology has spent a long time in development. Prototypes of Mavic’s first system, the Zap, made a cameo appearance at the 1992 Tour de France and the company introduced its second attempt, the Mektronic, in 1999.
For much of this decade, both Shimano, which dominates bicycle parts the way Microsoft dominates computer software, and its venerable Italian competitor Campagnolo occasionally tested prototype systems on the bikes of pro riders. More often than not, the prototypes were devoid of trademarks, presumably to limit embarrassment if results proved as unfortunate as the Zap.
The Campagnolo and Shimano systems share the basic design of current mechanical derailleurs. That is, a parallelogram that moves the chain back and forth and, in the rear, two spring-loaded wheels to keep the chain taut.
Two paddle-shaped electronic switches that sit behind the brake lever allow riders to shift gears. Tapping either paddle lightly in Di2 sends an electronic signal through a wire to a small motor inside the derailleur, moving the body and thus the chain by turning a worm gear. Even Devin Walton, a spokesman for Shimano, acknowledges that when it comes to the rear derailleur, there is little or no difference in shifting between the electronic and comparable mechanical offerings from the company.
The gains are move obvious, however, with the front derailleur, which moves the chain between the two large, toothed rings on the bicycle’s crank.
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