Originally Posted by
koiboy4343
we have tested our bike in a wind tunnel against a cannondale slice and the drag coeficient difference is somthing like .05 which is almost nothing according to the technition, and definitly not worth spending upwards of an extra 5K to get a .05 drag difference. so we are focusing on ways to change aero proportys (clinchers and aero bars) without spending stupid amounts of money for a barely noticeable change.
this research:
http://www.altairhyperworks.com/html...431_MNGodo.pdf
showes that maximum eficiancy happenes at a yaw of around 12 degrees and then drops sharply from there on wheels with the carbon clinchers only.
shaveing legs: 5 seconds difference on a 40K not 1:30.
Bicycles and Aerodynamics
your off by 94% and over estimated 18 times over.
also you would be suprised at how much efficiancy is lost due to hubs. besides wind resistance that is the largest loss of eficiancy from the whole bike.
It might be that your English isn't allowing you to express yourself clearly, but "carbon clinchers" covers such a wide assortment of wheels that it's impossible to generalize that they drop off at 12 degrees of yaw. For example, if you go
here and click on aero data, you'll see the drag reduces well beyond 12 degrees yaw. I understand the company has a vested interest in showing their wheels help but you'll find that although the exact values may be off here and there the general trends will still be there.
A recent wind tunnel test by Specialized. They have a distinct interest in showing that buying their equipment is best but in this case they found that a very simple act will give a bigger benefit than buying some of their equipment. I can't tell you how their testing protocol differs from other tests, like the one you cited (which I have seen before as it was significant when it first came out).
https://www.youtube.com/watch?v=DZnrE17Jg3I
I'm not trying to give you a hard time, I want to help. I think that this is a really interesting challenge and pertinent to my own transportation thoughts/needs/wants.