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Old 08-28-2016, 03:23 PM   #9 (permalink)
Grant-53
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Join Date: Feb 2010
Location: Elmira, NY
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There are a number of ways to smooth the air flow behind the rider. The key dimensions are the rider's shoulder width and back angle. On my bicycle my shoulders are 20 inches wide and my hips are 17 inches. My back angle is 60 degrees from horizontal. For good stability in all winds, testing done by the Specialized bike company for their aero tubing found a 5 to 1 aspect ratio foil trimmed to a Kamm length of 75 % of the original to be optimum for their road racing bike. So I would shape a body (5 x 20 inches = 100 inches) with the tail cut off at 75 inches from the nose. The tail box would fit tight behind the rider from the shoulders to the seat. The top of the box could taper down about 4 degrees. Two bulkheads and the base plate could be cut from 3/8" aluminum honeycomb or plywood and the skin from a couple wastebaskets or sheet ABS.

Last edited by Grant-53; 08-28-2016 at 03:32 PM..
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