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New Castelli Split Second Jersey Flies in the Wind Tunnel
For Immediate Release: December 1, 2006
New Castelli Split Second Jersey Does More Than Look Fast and Feel Fast. It is Fast – With Wind-Tunnel Data that Proves It
SAN DIEGO, Calif. – Perhaps Castelli named its new Split Second Jersey – available Spring 2007 – a bit too modestly. Fifty-Eight Second Jersey would be more accurate.
Recent aerodynamic testing at the renowned 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. To put that in perspective, it’s the equivalent performance gain of equipping one’s bike with high-profile, carbon-fiber wheels – at a fraction of the cost.
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. 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.
Moreover, the Split Second jersey was tested on a regular road bike with dropped handlebars, not an aerobar-equipped TT bike. Riding on the tops of the bars in the Castelli Split Second jersey is actually faster than riding on the hoods in a normal jersey. Plus, it’s not a skinsuit; it’s a fully functional, every-day jersey, featuring wicking fabric, three pockets, and a 10-inch zipper.
“We figured the Split Second Jersey would show a gain in performance, but we were surprised by how much of an improvement we saw,” announced Castelli Marketing Director Steve Smith. “We’ve created a fast jersey for every-day performance. Castelli has always prided itself on developing clothing that makes riders, average and elite, faster – performance-enhancing clothing, if you will – and the Split Second Jersey continues that tradition.”
Test conditions replicated a hard road ride or breakaway with a 5-10, 160-lb. rider on flat terrain. Wind speed was approximately 25 mph and side winds of 0-, 10-, and 20-degrees. The reference jersey was a standard Castelli model in its ProCool fabric with a race fit (size M on the test rider).
WHY IS IT SO FAST?
FIT and CUT. The Castelli Split Second jersey was designed with no extra fabric flapping in the riding position. The cut is small and stretched tightly over the body, with extra-long sleeves that point up and forward. This fit pulls across the rider’s chest and shoulders when standing up yet feels comfortable when on the bike. A flap smoothes airflow over the back pockets. The neck cut allows the jersey to lie flat on the back.
FABRIC. The Split Second utilizes a fine microfiber nylon/Lycra® fabric – called Velocity – that lets the air flow smoothly over the surface. And the extreme stretchiness of this fabric allows the jersey’s wrinkle- and flap-free cut and fit.
AIR FLOW. To get air to flow efficiently over a rider’s body, the front surfaces of the jersey were made as smooth as possible, with all seams placed outside the air flow; folds and flapping fabric were minimized. In addition, Castelli designers added sections of dimpled fabric (think golf ball) that create “induced” turbulence. This reduces drag by “detaching” the air from the jersey surface. To prove the effectiveness of the dimpled fabric, Castelli tested a jersey without the dimples; the dimples created a five-watt savings.
The performance-enhancing Castelli Split Second Jersey will be in stores in February 2007. However, the technology will make its debut on the Pro-Tour jersey for the Saunier Duval-Prodir Team, which will be supplied by Castelli for the upcoming season.