Home Made Aero Spin Down Test of 2 Top Wheels

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WMW
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Joined: Sun Jul 29, 2012 2:59 pm
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by WMW

cyclespeed wrote:The results might surprise you!
https://www.youtube.com/watch?v=guV_R9_qwtA


If you are interested in gleaning more information from a spin down test, check this out. http://www.bikephysics.com/wheel.pdf

Also, do you live in a palace?
formerly rruff...

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cyclespeed
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by cyclespeed

WMW wrote:
cyclespeed wrote:The results might surprise you!
https://www.youtube.com/watch?v=guV_R9_qwtA


If you are interested in gleaning more information from a spin down test, check this out. http://www.bikephysics.com/wheel.pdf

Also, do you live in a palace?


Interesting read that concludes;

a) drag force on the spinning wheel increases with the square of rotational speed
b) power required to keep the wheel at that speed increases with cube of speed
c) it is possible to differentiate differences in wheels' performance with this type of test, his being substantially more detailed and accurate than mine....of course it's a far from perfect test as translational (forward motion) aero is not considered, but if a wheel proves itself aero in the stationary test, then it would be reasonable to assume that it would also perform well, if slightly differently, in a moving spin test, above all at 0' yaw.

A shame he only managed to get the wheel up to 35km/h or so, as the aero affects only really manifest themselves significantly at higher speeds. But even if you're the best bongo drum player in the world, you can't do more than about 30 by hand, and his 'floss' trick only got him another 5. He needs a drill!

No, not a palace, a chateau!

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