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Old 04-20-2008, 12:56 PM   #9 (permalink)
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Originally Posted by trebuchet03 View Post
I agree with exactly what otto said in response ...

Hey Tre, here's a related but somewhat roundabout question:

Dr. Alex Strojnik was one of the great thinkers and designers of laminar flow light planes, designer of the Strojnik S-2 and author of a trilogy of great books on efficient design. His S-2 (Google for it) motorized sailplane had tandem fixed wheels, about a foot diameter each, and closely spaced. He found out that two wheels in tandem had less drag than one alone, as the second acted as a wake fairing for the front one. NASCAR drivers, Tour de France bicyclists, et al have long known the benefits of drafting, which are well established.

So, here's the question for you in particular, being an HPV guy: Why not have two tandem smaller wheels in the front of your HPV streamliner, instead of one larger one? These could much more easily be faired, would fit better under the nose, with considerably less wetted and frontal area. This would also make for less bulbous nose, as you'd not need to include the big front wheel in the same faired volume as your pedal pathways.

Rolling resistance is always an issue, as it adds to total drag the rider must overcome. Has anybody tested the difference between rolling resistance of smaller, solid wheels vs. larger inflated ones? At what point would the lower air drag of smaller tandem wheels be a net advantage over the presumably lower rolling resistance of a bigger wheel?

Sorry about the hijack, my excuse is that it all relates to the drafting-as-drag-reduction thread.
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