Wrong Crank Length - Way to Correct?

1

I recently put on new cranks and realized when my post ride told me I increased my FTP by 28W (I wish!) yesterday, that I forgot to change the crank length in my Wahoo Elemnt Bolt v2 from 172.5 to 165. Is there a way to correct this in the .fit file so that it’s recorded correctly in my training data?

2

In Intervals you can edit the power with a fixed offset or a multiplier + offset. Activity page, Actions, Fix data.
In this case a multiplier derived from your actual FTP and the ´false´ new FTP, should be pretty accurate. Normal/Inflated.

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3

Thanks. The crank arm is 4.55% shorter, so power should be overstated by that amount. So I will fix data by that amount. Much appreciated!

4

What type of power meter do you use? Only pedal based power needs correct crank length. For any other power meter it shouldn’t matter.

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Yes, pedal-based power meter (Favero Assioma). I believe it’s just a 4.5% correction since 172.5mm is 4.5% longer than 165mm.

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Now that I’ve fixed the over-reported power by scaling the power to 95.45%, I would like to export the fixed file and upload to Strava. Maybe I’m daft, but I don’t see where to down the file from intervals.icu. If this can be done – I’m surprised if it cannot – can somebody point me in the right direction?

Thanks so much!

7

Activity Interval Data page.
Fit File. Select both power and HR.

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