Do you still do spindown calibrations for your Kickr if it has auto calibration?

This is a mix of a question and FYI for the community I guess. I have a Kickr Core and it’s among the models listed as having auto calibration with the latest firmware.

I checked it against my Assioma Duos back in January or so when I was doing alot of indoor training, and the Kickr tracked well (if maybe 1-2% higher) than my pedals. No big deal of course and I felt I could trust the power on both PMs. I decided to check again a few days ago and the Kickr was ~5% higher than my Assiomas. I have the latest firmware and it should be set to auto calibrate. I did a factory spindown today and a test workout. Now the Assiomas are ~2% higher than the Kickr which makes sense given where they’re measuring power and any drive train losses.

I was prompted to check because I’ve been struggling with harder efforts on the trainer lately, and I’d chalked that up to a mix of fatigue and greatly prefering to ride outside this time of year. I guess inadvertently doing longer threshold intervals at 105% in a hot, humid basement can make you question your life choices :rofl:

Not sure if other folks have run into similar issue with their Kickrs. Might be worth performing spindowns even if they supposedly are no longer required :thinking:

I still do spindowns from time to time on my KICKR CORE. Especially this time of the year when I’m not consistently on my trainer and only really use it if the weather is too bad to get outside which means it might be a week or two between uses.

With the humidity and temperature changes around here, I’ve found that my KICKR doesn’t always feel super accurate if it’s sat unused for a while. I’ll usually perform a spindown after the warmup period of my workout and there is a noticeable difference afterward.

My thoughts around this are that the new auto-calibration feature relies on coasting to get a reading on resistance (I think) and when using TR I’m never coasting, so things wouldn’t calibrate until the end of the workout. :man_shrugging:

In the winter when I’m on the trainer 5 days a week I don’t find this to be as much of an issue though.


Thanks Eddie! Glad I’m not alone because it’s easy to go a little crazy worrying about this stuff :rofl: Great point about coasting too!

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I totally get it. :sweat_smile:

At the end of the day, it’s impossible to say which source is accurate, so I find that calibrating when needed is the most you can do to keep things on point.

Trust yourself too and when something feels off, it probably is!


I’d assume the end of every session, unless you turn it off literally on the last pedal stroke.

Still, I’ll keep doing the odd spindown every so often myself as well I think!


Bingo. Which is likely fine IMO, since the trainer is well warmed up at that point. And presuming the trainer stays in the same space under relatively similar conditions, it is good to go for the next ride.

I just had this issue last week! I was failing and putting in way more effort into what were supposed to be easy workouts. I had calibrated things at the start of the block and didn’t think about it. Turns out, my Assioma and kickr snap were reading 50 watts difference. I calibrated and everything is just peachy. Who would have thought to do the thing that Wahoo says to do every session would have such a dramatic effect lol


I tend to do the secret factory spin down once every 6 months and a regular spin down if there have been any major temp changes or I’ve moved my trainer for cleaning. Other than that it seems to stay relatively in line with my P2Max PM.

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