Weird power numbers during workout

Trainer - Wahoo kickr core firmware fully up to date and calibrated

My Workout - SST
5 min warm up
5 min @ 210 watts
5 min @ 190 watts
5 min @ 210 watts
5 min @ 190 watts
5 min @ 150 watts
5 min @ 210 watts
5 min @ 190 watts
5 min @ 210 watts
5 min @ 190 watts
5 min warm down

Anyway i’d noticed in previous workouts that the numbers i was hitting in each block seemed weird. So in the 210 blocks on the app and laptop it was always 208/209 and didn’t seem to hit 210. I could get it to hit 210 no matter what i did
In the 190 blocks is was always 190+, usually 191 and 192

So i tested the kickr using the kickr app in erg mode and set it to 210 and it held 210 no problem at all.

This morning same was happening again. So as another test in the second set of blocks i upped the bias by 1%. It still said hold 210 but was now consistently 210+. Weird thing here though is the 190 blocks were now 195 blocks but it was always 193 or 194 again no matter what i did.

The only times i could get it to jump about the required wattage when it was being weird was to do a random out the saddle burst but then it would settle again.

Just seems very odd to me. I also felt that when i upped the bias to 101% the 210 blocks did seem noticeably tougher even though the req watts was the same and i was, according to the numbers, only 2 watts more output then when bias was 100.


This has to do with your FTP settings.
It will calculate your zones from your ftp, for instance:

5 min @ 210 is probably 207 with your ftp settings. But ingame the erg mode will not keep you on that specific number so it shows the 210 but fluctuates a little underneath it.

Just try to ride on 101% and it will probably be at 210 or even go up to about 212/213.
But my advice would be so disable the erg smoothing in the Wahoo app. Than it will show the real watts that your riding during erg mode.
The numbers will be jumping arround a little more but it prefer to see the real numbers i’m pushing.

Good luck,
Hopefully this helped

Thanks for the response.

So the erg smoothing in the Wahoo app will affect whats going on in Zwift?

I will have a look at that setting and see if it affects the numbers i’m seeing when i do the workout again.

Again thanks.

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