The “aero-slippery” bike jersey, from Castelli

Maybe Castelli named its new Split Second Jersey—available late-winter/spring 2007—a bit too modestly. Fifty-Eight Second Jersey would be more accurate.

Recent aerodynamic testing at the San Diego Low Speed Wind Tunnel determined that wearing the Castelli Split Second Jersey could shave nearly one minute off a rider’s time over a 40-kilometer distance.

After months of research and development, Castelli created a jersey that features a new “aero-slippery” fabric, a wrinkle-free fit, and critical areas of dimpled material.

Here’s the technical dope. . .

“In the wind tunnel, the Split Second jersey delivered a CxA drag coefficient of 0.359 compared to 0.377 for a standard Castelli jersey. In a zero cross-wind environment, this computes into a savings of 15 watts. And across various cross-wind measurements, the average savings was 13.8 watts—which equates to a 58 seconds savings over 40 kilometers at an approximate pace of 25 mph.”

Price will be $150. Watch for jacket availability.

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Stephen Regenold is Founder and Editor-In-Chief of GearJunkie, which he launched as a nationally-syndicated newspaper column in 2002. As a journalist and writer, Regenold has covered the outdoors industry for nearly two decades, including as a correspondent for the New York Times. A father of four small kids, Regenold and his wife live in Minneapolis.


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