pyf wrote:
pyf wrote:
Tom A. wrote:
That's right. So if it takes 250 watts to go 25mph with the old bike, now you can go 25mph with 244.5 watts. It's a marginal gain...but still a gain. Plus the new bike looks great...never a fan of the current one in the looks department.
Hmmm...I wonder what the front brake and front and rear brake cable housing loops on the previous gen were "worth"? ;-)
To calibrate y'all on the "cost" of brake cable housing, here's a little demo fixture I took some pictures of at the Win Tunnel a few weeks ago. These 2 objects have the same drag. The small cyclinder is the same outer diameter as a piece of cable housing.
Just sayin'...
Hi Tom,
Was listening to the FLO podcast with you the other day, and you reminding me of this super nice pic you posted.
Just trying to make my brain "clear" about this : like you say the cylinder and the aeroshape have the same drag coefficient "Cd" , but the frontal area "A" is still smaller for the cylinder. Thus the CdA (Cd x A) is still smaller for the small cylinder. Is that correct of am I missing something ?
Thanks
Ps : those two podcasts with you were great !
Actually, you have it the opposite way around. The CdAs of those 2 objects are the same, and thus the drag force is the same for each. Obviously, with the wing section having a so much larger A, it's Cd is significantly lower. Round sections perpendicular to the airflow have fairly high Cd.
One interesting thing they are illustrating on those demo units is that the drag on an object can be estimated by the size of the turbulent wake trailing the object. That's what those pairs of lines leading up to and after each shape represent.
I'm glad you enjoyed the podcasts. As painful as it is to hear one's own recorded voice, I thought they turned out well too. Thanks!
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