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Wheelset "Aero-ness" and rim width

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Wheelset "Aero-ness" and rim width

Old 04-08-09, 12:55 PM
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nikoncmk
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Wheelset "Aero-ness" and rim width

What is the difference is aerodymanics comparing rim height vs. rim width.



Do you buy the diagram below?


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Old 04-08-09, 01:22 PM
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merlinextraligh
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For those rims, that's likely true. But when you get into deepdish aero wheels its get more complicated and the shape of the rim affects tire sensitivity, and aerodynamic width.

http://www.zipp.com/_media/pdfs/technology/rimshape.pdf
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Old 04-08-09, 01:24 PM
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If you are really harping on the aerodynamics then in general you want to find a tire that will end up being the same width of the rim when mounted. Zipp supplies a tire that is intended to do that when mounted on their rims.
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Old 04-08-09, 03:23 PM
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I like the streamlines in the drawing, implying that one flow is turbulent and one isn't. Pretty sure both wold be turbulent.

Plus, the vortices are spinning the wrong way. Those would decrease drag!
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Old 04-08-09, 06:53 PM
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HED buys it with their C2 rim.
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Old 04-08-09, 08:17 PM
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With what little I remember of my Physics class, that diagram seems logical. In general, the narrower the rim the narrower a tire you'd want to use with it for that reason. How much of a real difference it makes... well that's where the icky math comes into play.
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Old 04-08-09, 11:14 PM
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HED C2 rims and Zipps 2009 Toroidal rims which, coincidentally, they share with HED are all wide rims...sometimes wide enough not to fit on most aero road bikes.
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