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Mass power scaler tool

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Mass power scaler tool

Old 05-31-22, 03:40 PM
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Seattle Forrest
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Mass power scaler tool

This came out of a question in the electronics forum, but might be useful to people in here too. For example if you have a single sided power meter and a known leg imbalance. It will update all of the power values in all the TCX files in a folder, by a percentage you specify. It saves a copy of the original file immediately before writing in case anything goes wrong or you change your mind. It is quick and dirty, but does the job.

https://github.com/CascadePass/TCXPo...eases/tag/v1.0
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Old 06-01-22, 09:09 AM
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RChung
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Would you use a 96% (or maybe 104% -- I don't remember which was the one-sided PM) scaling factor to adjust these data?


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Old 06-01-22, 12:31 PM
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Originally Posted by RChung View Post
Would you use a 96% (or maybe 104% -- I don't remember which was the one-sided PM) scaling factor to adjust these data?


Personally, I think my power meter works pretty well and doesn't have a consistent, systematic error, so I'll never use this software. But it was an easy problem to solve, there didn't seem to be anything already set up to make this easy, and I'm sure it will be of use to someone. 🙂
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Old 06-01-22, 01:26 PM
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Originally Posted by RChung View Post
Would you use a 96% (or maybe 104% -- I don't remember which was the one-sided PM) scaling factor to adjust these data?


For the reasons most folks want to do this, that actually is good enough. Especially if the person knows what ride they're doing it for, and why.

Lower intensity rides typically seem for me to have the higher imbalance. Imbalance approaching none at threshold. So for long Z2 rides I will apply a hamfisted 5% bonus to the ride so that the TSS score pans out closer to reality.

I will not do it for an interval ride where I care about the threshold stuff, that's already nearly at equal distribution.

I do this for a terrible left-only Stages knowing the power split from two Quarqs on other bikes that seem to agree with each other.

Would I ever use this for something like aero/CRR testing? Absolutely not.
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Old 06-01-22, 03:21 PM
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Originally Posted by burnthesheep View Post
For the reasons most folks want to do this, that actually is good enough.
You know how Stages sold their PM on the idea that consistency is all that matters, and everyone who bought one repeats that? If they really believed that, they'd just report the left side and not double it.
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Old 06-01-22, 03:55 PM
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My Garmin defaults to 172.5 mm cranks and mine are 175 mm. If I hadn't set it up properly from the start, that would be a good reason to rescale a bunch of files.
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Old 06-01-22, 06:55 PM
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That's a good reason.
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Old 06-01-22, 07:17 PM
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If I had put more effort into my ride, my power numbers would have been higher. That's a good reason to rescale my data -- to reflect what I could have done.
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Old 06-01-22, 07:25 PM
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Originally Posted by tomato coupe View Post
If I had put more effort into my ride, my power numbers would have been higher. That's a good reason to rescale my data -- to reflect what I could have done.
Now I should have used this reasoning on my race placings.
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Old 06-01-22, 07:38 PM
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Originally Posted by 79pmooney View Post
Now I should have used this reasoning on my race placings.
It puts me on the podium every time!
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Old 06-01-22, 09:27 PM
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Originally Posted by tomato coupe View Post
If I had put more effort into my ride, my power numbers would have been higher. That's a good reason to rescale my data -- to reflect what I could have done.
And let me enter what my weight would be if I didn't love tacos.

This was for somebody who wants to compare his power curve with two bikes that don't agree. I guess you could cheat but it would be a lot of work.
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Old 06-02-22, 09:33 PM
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Almost 15 years ago after a distasteful and infamous situation on another forum, someone put together an app that would inflate the power column of a data file by a chosen percentage. We called that the Joaquinizer.

Separately and independently, about a dozen years ago after a guy died while attempting a Strava KOM descent, someone else wrote an app to alter the speeds and times for Strava KOMs. I can't remember what that was called.
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