Powerstroke Ideal vs Real World

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blp
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Powerstroke Ideal vs Real World

Post by blp »

I apologize if this is covered elsewhere, I didn't see it.

I love PowerStroke - a real eye opener.

My problem (among many others) is trying to achieve a real world ideal pedal stroke. On flat ground I can see the achievable goal of perfect pedal pattern, but on steep climbs, i just can't see this as achievable. Is it achievable on 7+ % grades?

Are there sample files from, say, Team Columbia or other high level riders to see what is achievable from supremely trained riders on various terrain? I'm thinking '14 Giro or TdF.

Perhaps in the iBike blog, there can be an in-depth study of pedal stroke and how to extract the most from PS.

Thanks
Velocomp
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Re: Powerstroke Ideal vs Real World

Post by Velocomp »

Your question includes the answer...

On steep grades your body will inevitably accelerate and decelerate more during each pedal stroke. This is because gravity is tugging on you constantly.

In fact, PowerStroke reveals that, on hills, pedaling stroke difficulties are a "flaw" of conventional round-crank designs. You might try an oblong crank design, such as Rotor or Osymettric. These are designed to help even-out pedal stroke.
John Hamann
Pete
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Re: Powerstroke Ideal vs Real World

Post by Pete »

I just installed a Doval chainring on my son's bike ($15 off eBay) and will be watching to see how powerstroke patterns differ.
He tends to have a vertical oval shape on the powerstroke plots.
One thing I notice is you need ride segments of a 'reasonable' length to get smoth plots. Too short and they look like a star , or explosion even.
Velocomp
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Re: Powerstroke Ideal vs Real World

Post by Velocomp »

Pete wrote:I just installed a Doval chainring on my son's bike ($15 off eBay) and will be watching to see how powerstroke patterns differ.
He tends to have a vertical oval shape on the powerstroke plots.
One thing I notice is you need ride segments of a 'reasonable' length to get smoth plots. Too short and they look like a star , or explosion even.
Yes. As is in all things, more data is better.
John Hamann
blp
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Re: Powerstroke Ideal vs Real World

Post by blp »

Yes, I agree about the length of the segments. My rides are a minimum of 1 hour and the plot for the total ride is very different than shorter segments. Steep climbs are another thing altogether.

I am looking at Doval rings too. Like to hear your son's experiences Pete.
blp
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Re: Powerstroke Ideal vs Real World

Post by blp »

I am finding PS very helpful in correcting my pedaling technique.

I had a couple of knee injuries (hockey of course, I'm Canadian), and one knee has a torn PCL which is now structurally not as stable. It would be interesting to see how different that leg is vs the other , vis-a-vis power propulsion, wasted joule, etc.Is the difference muscular or structural?

Is there a way to show the PS stats right / left in the next FW/SW updates?
Velocomp
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Re: Powerstroke Ideal vs Real World

Post by Velocomp »

We already show left/right split in the wasted watts window. PS involves extremely complicated software calculations that, right now, are too complicated for the microprocessor inside the Newton.
John Hamann
blp
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Re: Powerstroke Ideal vs Real World

Post by blp »

Thanks, but I don't see R/L split in Wasted Watts window. The fields I see are:

Selection Distance: 25.42 km
Ride Time: 1:03:46
Propulsion Power: 147 W

Wasted Watts: 3 W
38% Due to Side-to-Side Motion
62% Due to Front-to-Back Motion
Total Wasted Joules: 13 kJ
Total Wasted Motion: 167 m
Wasted Time: 0:00:34

Am I looking in the right place?
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Velocomp
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Re: Powerstroke Ideal vs Real World

Post by Velocomp »

I apologize, I misspoke. We report side-to-side and front-to-back wasted motion. We don't break this out by leg, since both legs contribute to both motions.
John Hamann
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