Power Drift (Kickr on Trainerroad vs Garmin reading Stages Power)

Glassy workout was on my calendar tonight, was pretty thrashed from 5+ hours driving yesterday and general lack of sleep last night. Needed to take multiple breaks during the last interval, argh.

Stages power vs Kickr reported power:

unfortunately from a DCRainmaker analyzer tool point of view, TR does wacky things in TCX file after workout pauses. So ignore the last interval as time doesn’t align. In general things are good until the 3rd interval when cadence drops and then Stages PM is reporting higher power than Kickr. I don’t know where the problem is…

I’m within 3 watts over 20 minutes on the power duration curve:

And I’m traveling all day tomorrow, so maybe it is time for an aerobic endurance ride on Thursday and Friday. I’ll keep collecting and analyzing data, for now its looking good after giving new pedals and power meter a chance to settle down. But still, not happy how two power charts start to diverge once cadence drops, or I stop and take a short break.

I have a Stages in Powermatch on the 2018 Kickr (and had 2015 Snap before that) and use ERG exclusively. For high wattage intervals, my experience is that it’s typical to see 1% spikes up and down (so 280 to 320 during a 300 watt interval) that look exactly like your workouts.

I think I’m missing what you’re expecting to see. To me both of your workout charts look the same here (the E-Motion roller 1:00 workout and the Kickr 0:12 workout). The 1:00 workout looks smoother, but I think that’s just because the scale has changed.

Here’s Boarstone (2:00) which looks pretty smooth:

And here’s a Ramp Test (0:26) which is very spikey and uneven:
12%20PM

These are days apart using the exact same equipment

I was having some issues with Powermatch and a friend offered to do a test with his 2018 Kickr and Garmin power pedals. We tried multiple combinations.

I rode the beginning of Abbot on his bike, on his Kickr with his pedals. Power graph on TR was fairly smooth and it tracked the reading of the Garmin pedals (on a Garmin 520) well. His system in Powermatched.

I rode the beginning of Abbot on my bike with Stages crank on his Kickr and his TR (after all the pairing and Powermatching was complete). The graph was not quite as smooth but tracked the watts required by TR well enough, usually +/-5W on the Garmin 520

He paired his Garmin pedals with my Kickr (Powermatch set) and rode the beginning of Abbot. The power readings on TR were not tracking well, swinging -5 to +15W during the rides warm up phase. When the 300W interval started he increased his effort. TR was requiring 300W but read as high as 458W while the Garmin 520 never read above above 340W. TR then settled in around 280W while the Garmin 520 read his pedals at 320-330W. The whole time TR was supposed to be 300W. Both were Garmin readings and TR were set to 10sec smoothing.

Can conclude from this that my Kickr has a serious issue and it’s not something with TR?

I looked for a simmilar forum on the Wahoo site and couldn’t find anything. Does anyone know of a very helpful resource like this at Wahoo?

I seem to remember Nate saying on the Podcast that Powermatch uses machine learning to get better over time. I wonder if the discrepancy between your KICKR and TR versus your friend’s is because his TR account has been running Powermatch a lot longer with his smart trainer and power meter?

Sold my 2018 Kickr. Currently on 11 year old eMotion rollers and Stages power meter manually matching power on TR. May try a Tacx Neo 2. Going to scour some forums and see what issues people are having first this time.

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