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Old 11-03-11, 17:37
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And, this is only considering the affect of crank length on power and ignores the potential aerodynamic benefits
Aerodynamic benefits the majority can achieve without changing crank length.
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Old 11-03-11, 21:01
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Aerodynamic benefits the majority can achieve without changing crank length.
Actually, I'll take John Cobb's stance on aerodynamic positioning over yours. thanks!
  #893  
Old 11-03-11, 21:56
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I will take data over opinion if that is okay with people.
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  #894  
Old 11-04-11, 01:13
FrankDay FrankDay is offline
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I will take data over opinion if that is okay with people.
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  #895  
Old 11-04-11, 01:18
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That is not data, that is an opinion with some numbers associated to it. Bit like a marketing claim that product X improves power by 40%.

Now if you had the wind tunnel data showing this chaps frontal area had improved by 30% in one aero position from another and power data showing a 25 min improvement in an Ironman you might have a case.
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Old 11-04-11, 02:39
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But, by the same token, what is the evidence that "longer" cranks is superior or that the "appropriately added leverage via longer cranks is unique to individual riders".

The Sheldon Brown article points out the issue very clearly. The only "leverage" that matters is the total leverage between the pedal and the ground. Since power is simply a matter of average force on the pedal and pedal speed it is clear that we should be looking at how crank length affects ones ability to apply that average force to the pedals thousands of time an hour. Since it is obvious crank length affects the ROM and angles the hip and knee joints I think we can assume there would be an effect. Where are the studies that look at the effect? Nowhere that I can see. So, while you may not be convinced by my musing and the reports of others, I don't see why you would think anyone would find your point of view any more convincing in view of the lack of scientific support for it.

And, this is only considering the affect of crank length on power and ignores the potential aerodynamic benefits
"pedal and the ground"? Sounds like using 90 degrees of rotation is your total basis for pedal stroke and "aerodynamics" picks up the slack. My view should be more convincing as it is backed by the performances World Champions and the World records of the riders using the techniques.
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Old 11-04-11, 03:53
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Originally Posted by CoachFergie View Post
That is not data, that is an opinion
"...I conducted a wind tunnel test..."-John Cobb

and btw, no one is claiming 30% reduction in frontal area. but the world's foremost authority on aerodynamics in cycling has seen a 30% reduction in "DRAG".
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Old 11-04-11, 03:58
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"pedal and the ground"? Sounds like using 90 degrees of rotation is your total basis for pedal stroke and "aerodynamics" picks up the slack. My view should be more convincing as it is backed by the performances World Champions and the World records of the riders using the techniques.
I think you are misunderstanding. "pedal to ground" meaning distance your foot travels vs. distance the rubber on your tire travels across the road. your "view" takes into account no variables. put those same elite riders on shorter cranks with gearing to correct for the gain ratio, and I'm willing to bet they'd be faster.
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Old 11-04-11, 04:24
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"...I conducted a wind tunnel test..."-John Cobb

and btw, no one is claiming 30% reduction in frontal area. but the world's foremost authority on aerodynamics in cycling has seen a 30% reduction in "DRAG".
Then he will be able to provide the numbers that showed a rider saw a 30% reduction in drag from one aero position to another just from a change in crank length.

Still says nothing about whether they can maintain power in that position or can hold that position for the an Ironman cycle section.

Till then your opinion on his opinion has been duly noted.
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Old 11-04-11, 05:13
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I think you are misunderstanding. "pedal to ground" meaning distance your foot travels vs. distance the rubber on your tire travels across the road. your "view" takes into account no variables. put those same elite riders on shorter cranks with gearing to correct for the gain ratio, and I'm willing to bet they'd be faster.
Perhaps you're correct about misunderstanding your "data". As I've pointed out I've been exposed to those elite riders for some time. They train on the track, in wind tunnels and have explored crank lengths. Some I've trained with from early teens to World team and they are willing to try everything so very few variables went unexplored. As for betting...how much do you have? Probably a stake in Frank's company? Sorry, that's a sucker bet.
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