Crank Aero Position?

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Crank Aero Position?

Postby Downhill » Sun Apr 22, 2012 10:44 pm

Well I've just got to ask...

Does crank position have any significant effect on aero drag?

If so, what's the best position when coasting in a straight line at high speed? 12 O'clock / 6 O'clock, or 9 and 3?
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by BNA » Mon Apr 23, 2012 9:50 am

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Re: Crank Aero Position?

Postby Alex Simmons/RST » Mon Apr 23, 2012 9:50 am

Do some virtual elevation analysis of coast down tests and you could work it out. Need a good high frequency accurate speed logger (speed every second is just enough, provided speed data is measured to nearest 0.2km/h) and a calm day. And a hill with a flat top approach, downhill section and a flat run off area at bottom is ideal.
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Re: Crank Aero Position?

Postby brentono » Mon Apr 23, 2012 10:08 am

To take a logical approach, and from much observation and a lot of personal experience,
it would have to be 9 and 3!
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Re: Crank Aero Position?

Postby JV911 » Mon Apr 23, 2012 10:28 am

most of the pros seem to coast at 9 and 3
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Re: Crank Aero Position?

Postby DavidI » Tue Apr 24, 2012 8:53 am

My recollection of various magazine articles based on wind tunnel testing is that the best position is, as stated, 9 & 3.
As to whether it has a "significant" effect... well, that depends on what you consider "significant." :wink:
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Re: Crank Aero Position?

Postby foo on patrol » Wed Apr 25, 2012 8:33 am

Keep pedalling softy! :mrgreen: Yep 9/3. :wink:

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Re: Crank Aero Position?

Postby Downhill » Wed Apr 25, 2012 12:56 pm

foo on patrol wrote:Keep pedalling softy! :mrgreen: Yep 9/3. :wink:

Foo


But I've run out of gears!!! :mrgreen: :mrgreen:
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Re: Crank Aero Position?

Postby foo on patrol » Wed Apr 25, 2012 3:10 pm

Well try harder! :roll: :lol:

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Re: Crank Aero Position?

Postby hannos » Thu Apr 26, 2012 4:04 pm

JV911 wrote:most of the pros seem to coast at 9 and 3



well they're wrong!

It's 3 and 9!
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Re: Crank Aero Position?

Postby foo on patrol » Sat Apr 28, 2012 5:43 pm

^^ Idiot! ^^ :lol:

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Re: Crank Aero Position?

Postby Downhill » Sat Apr 28, 2012 8:39 pm

hannos wrote:
JV911 wrote:most of the pros seem to coast at 9 and 3



well they're wrong!

It's 3 and 9!


... but only if you're left handed! :mrgreen:
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