First time on a trainer, I noticed my power seemed down, so I compared the Kickr to the Assioma pedals. Am I understanding this right? Seems quite a lot out of range? If so, I guess I’ll get onto them, but I wanted to ask here first.
I suspect they will tell you that the Assiomas at +/-1% plus the Core at +/-2% plus some expected power loss in the drivetrain puts that difference within what they will call an acceptable range.
Make sure you do a zero reset on the pedals, and that they are set to the correct crank arm length.
I personally cannot get my Pro RS pedals to calculate normally when my recording device sets the crank arm length (be it watch or Edge unit), and just have to set it through the phone app whenever I feel the need to make any other changes or reset them or update them; so if I set the crank arm length and never connect to them via the phone app things seem correct.
Those numbers do seem a bit far apart IMO, but they don’t cross paths or have any unusual looking angles on the power curve so at least they trend correctly which likely means the crank arm length is set correctly.
Maybe just a calibration on both and look at it again.
Otherwise, yeah unfortunately those differences are quite high, but again, at least it’s consistent, which is more of what you’re looking for.
Everything is calibrated, it was my first ever ride on the kicker though so maybe it needs to run a few times. Thanks.
I’ve had similar experiences with Core 2 and Favero Assioma RS2 pedals. See:
https://forums.zwift.com/t/does-it-make-sense-to-use-pedals-with-power-measurement-in-zwift
As @Paulk wrote, the discrepancies are acceptable. The Core 2 is an entry-level model and not a calibrated precision device. The physics behind the measurement are also different. That’s why I interpret the differences in short or high power spikes with the Core 2 as being due, for example, to the flywheel’s latency as opposed to the Favero pedals.
After calibrating the Core 2 using Wahoo’s method:
the deviations are “super” and “ok.” Of course, depending on your point of view, where are the absolute values 
I have, but do not use anymore, P1 pedals and, compared to my H3 trainer, read a bit lower…say 3-5% typically. I now use a Quarq chainring PM and a KickrV6…the Kickr typically reads 5-10% lower. I do see temperature fluctuations from Winter to Summer…my HVAC cannot always keep up with Central Texas heat and I can see the Zero Calibration of the Quarq drift. I have not done a Kickr factory spindown in several months so maybe due. I probably need to do for each season. I have also not looked up the “proper” pedal sequencing for the auto-calibration. I think it includes coasting and one loses drops coasting.
One thing I have noticed is the Kickr does not pick up peaks very well. Cranking a few spins hard the Quarq will peak 50-60 watts higher. It is hard to track real time because the Kickr is always a few seconds delayed. I do not race much and never at the front so I am not overly bothered to analyze too much. I am pretty sure I have 3-second avg on both setups. I would put my P1s back on for a triple power measurement but I no longer have any road shoes and road pedals do not fit on MB shoes…at least the ones I have.
I also noticed with the Core 2 that short power spikes are smoothed out.
I use the Core 2 with Wi-Fi. This results in delays of 1 second. Recorded Assioma RS2 pedals with a Garmin Edge compared to Core 2.
And this setting:
I’m not sure if this setting affects the performance settings as well, or just the display.
Instant vs 3 second setting only affects what you see on the HUD.
Thanks, @Paul, for the clarification—good to know 