Reading all of these threads over the years makes me glad I kept my original Kickr, never a problem. It’s not quiet but I’m not upgrading. Sorry didn’t mean to derail this thread.
Well, when performing a factory spindown, Wahoo-app tells you to warm up/spin for 3 minutes, thats not even close to 30-45 minutes.
Wahoo tells you the Kickr has temperature compensation, auto-calibration and +/-1% accuracy, they say nothing about this not being the case for first 30-45 minutes of workout.
Im a noob when it comes to resistance units/eddy current brakes, but except that one belt, what is the differences between Neo and Kickr? I have never seen any drift in the Neo.
Edit. And fwiw, the small drift Im now seeing is probably temperature related. But the drift I experienced earlier did also include those “power jumps”, these I think where cadence-related and seems to have dissapeared after factory spindown.
So it seems like this drift over time is a feature of v5 units then?
Just done the above TR workout. First set was 2% lower second set 4% lower and last 6% lower.
Interesting that my kickr was reading 10% high at the start of the workout so I triggered a spindown calibration by coasting for 2-3 seconds during the warmup section and that brought the power readings to within 0.5% - but a similar spindown near the end of the workout had no effect at all.
Basically it seems you cant “calibrate away” the drift like you can on other trainers.
I’m hopeful that its just a case of them having to tweek the temperature compensation factor a little?
Regression towards the mean means that you’ll never be able to mathematically fully adjust for (calibrate away) the effects of things like heat-induced drift. A better engineering solution is therefore to minimize such drift in the first place.
This looks very much like my earlier sets, I would try doing a factory spindown post workout/long warm up.
Already tried that once 
I would give it at least one more try.
Yeah I will do - i’ve opened a support ticket too so we will see what they come back with if anything.
I just thought it was interesting that the two automatic spindown calibrations at different temperatures appeared to give the same calibration offset.
Usually I’d expect:
Spindown-time @ tempA to lead to offset value at tempA
And
Spindown-time @ tempB to lead to offset value at tempB
But in my case the calculated offsets seemed the same which to me would indicate that the spindown calculations themselves were temperature adjusted.
Also, in my experience power meters seem to usually read higher when they are warm? Almost like my kickr is overcompensating for a temp increase?
All just conjecture I agree - just finding it interesting
It was an automatic spindown during a workout so no figure was quoted… Just mean that the “warm” spindown didn’t make any difference to the power readings so it must have been similar to the “cold” one.
Initial contact from wahoo saying that they have not seen this issue before and will look into it - impressed with how quickly they responded though 
Really makes me wonder what type of testing these manufacturers do. If you don’t test much, you won’t find problems. Success!!!
I was quite skeptical of the ‘no calibration required’ on new kickrs, as with the greater use of mechanical components (ie belt, etc) compared to the Neo* trainers made this seem sketchy. It may be as simple as they need to tell people to coast for N seconds periodically, but they should at least be honest about how the auto calibration works.
They key difference I see here is: Neo* trainers don’t do calibration. Kickr v5 does auto calibration, but relies on certain unspecified ride characteristics (ie coasting) to do this.
I wonder how wahoo tells the difference between coasting, with no pedaling, and just pedaling slower than the flyhweel is spinning (or backpedaling vigorously)? In both cases the flywheel will be slowing down, but there will be different levels of drag being measured in each case.
I’ve noticed the same issue with the drift on my kickr v5 and what I would recommend to do is a factory spindown after a long workout.
Just wanted to elaborate, for me I believe my earlier drift was the sum of two effects:
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The drift Im now seeing and that was similiar for my Kickr18, that I believe is 100% temperature related.
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The “power jumps” (seen under) I experienced multiple times during workouts earlier that seems to have disappeared after the post workout factory spindown.
Just as an update. I’ve done 3 fairly long trainerroad workouts in a row now in which the difference between my favero pedals and my kickr V5 have stayed within 1-1.5%.
I cant complain at all if it stays like that.
Did you do a second factory spindown? You had some drift 7 days ago right?
Looking at my own data from the last week, it seems like things are getting gradually worse, not much, but its a trend, will probably do another factory spindown tonight.
To be honest I’m starting to doubt my pedals… the biggest change between my original workouts and the latest ones is that i’ve brought my bike into the house a couple of hours before my workout rather than just 15-30 mins. I also removed and re-seated my pedals - but they seemed fine.
I still get some drift in the same direction as before but now my kickr is going from +0.5% to -1.5% compared to my pedals…
I’m going to keep an eye on it obviously but at the moment I think the kickr is going to fulfill my aim of being close enough to my pedals that I don’t have to religiously use powermatch.
Been following along here after picking up the new v5 Kickr and already had the Assioma Duos. I seem to be seeing some “drift” where the pedals start reading higher (or Kickr lower) in ERG mode, but the weird part here is I have the Wahoo app set to “control from ANT+ power meter” with the Assioma ID in there. Does that make any sense?
Today’s ride as an example. Starts out pretty close, then drifts to ~5-10W higher on pedals, despite the Kickr in theory using that as the power source. I don’t expect instant power to match but I expect 15 min intervals to land within a couple watts. Is my expectation off?
I have no experience with the “control from ANT+ power meter” feature, but thought that was Wahoos own “power match” feature. So would expect graphs to line up pretty close to each other, that isnt the case in the dataset over. Doesnt seem to work at all.
I would toggle off the “control from ANT+ power meter”, set power source to Assioma Duos and controllable to Kickr in Zwift, then I would expect the Assiomas to hit the ERG-target.
I’m happy with my kickr now…
I still get a little drift in the same direction but it remains (just) within the combined accuracy. Kickr starts +1% and ends -1.6%
So they are drifting 2.6% over the hour which isn’t ideal but they do line up exactly around the middle when they intersect 
I calibrated both PMs after the warmup - zero cal on the pedals and just relied the auto cal on the kickr. Suppose my next experiment would be to trigger an auto cal on the kickr before the last set to see what difference it makes.
Mine has been drifting about the same for couple of weeks now, Quarq reading from -3% in start to -0% in end of workout. Looked like the drift was getting gradually worse over those weeks so did a new factory spindown after workout november 20. On workout november 21 Quarq was back to reading from 0% in start and +4% in end of workout including those power jumps mentioned earlier, so did a new factory spindown after workout november 21. On november 22 Quarq was back to reading from -3% in start to 0% in end of workout.
Nov20: DC Rainmaker Analyzer
Nov21: DC Rainmaker Analyzer
Nov22: DC Rainmaker Analyzer
Dont know what to take from this, if anything.
Found out last week that the KickrV5 isnt compatible with the 2021 Emonda, which I have ordered for next year. So I will probably ask my bikeshop if they will give me a deal on the Neo 2T. Which is a bummer since I sold my 2T to buy the Kickr, but I really dislike this drift.