Kickr resistance spikes and spindown failures

Hoping somebody can help as a search didn’t find any solutions…

I have a Kickr gen 1 - its always been bombproof but hasn’t had that much use in the last couple of years. I’ve done a few sessions this week and have 2 issues happening every session:

  1. random resistance spikes in both ERG AND resistance mode. No death spiral but randomly adds 20-30w of extra resistance for a few seconds. Today it seemed to do it every minute or so during some longer vo2 intervals

  2. spindown calibration repeatedly shows a failure message - sometimes after its being spinning down for a while and sometimes as soon as I stopped pedalling. Last time it failed about 5 times and then succeeded and today it failed about 10 times and I gave up trying. Always done via the TR desktop app.
    Edit - just used the Wahoo app and it performed the spindown perfectly 1st time.

Any advice on what may be happening or any potential fix? Wondering if this is a TR issue or the Kickr may be on the way out? Its always been very steady in the past except for the ‘once in a blue moon’ death spiral maybe every few months…


EDIT: Just to wrap this up in case others suffer the same issue - seems that the spikes were caused by interference from my Wahoo head unit also recording the session. Switchimg that off and having only TR running solved all the issues today.

I have a Kickr Core from 2019 and started running into random resistance spikes, although not as often as you. This was after some months of no problems. Sometimes they stretched out for a pretty long time. I was running TR on my PC laptop while watching videos on a second monitor. After a bit of tinkering with no success, I gave up and started running TR on my Android app. No more spikes.

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thanks - I’ll try a different laptop tomorrow andmaybe the app, but do like being able to see the UI on a good sized screen. Seems like it may be Tr rather than my Kickr though.

I ping’d Wahoo support so hopefully they’ll come back with something as they are always very responsive.

I have a gen 1 Kicker as well and have used it pretty consistently over the last few years. I used to get a couple of spikes per hour but I moved a few months ago and since then really haven’t experienced spikes. These spikes are usually due to interference of some type. Some things to try:

  • Move your PC closer to your trainer.
  • Changing the wifi channel on you router may help.
  • If you are using bluetooth you may want to try using ANT+ or vice versa.

I run TR on an iPhone (using BT) and usually run Zwift on a Macbook (using ANT+) concurrently.
I have had issues with the spindown calibration as well. For me it could be related to running TR and Zwift concurrently. I have found that using the shortcut smarttrainer spindown almost always fails, but if I go into devices and select the kicker and then do the spindown from there it usually works. If you continue to have issues you should contact TR support. They can sometimes look at the data and see what is going on.

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thanks - I’ll work on the connection stuff. I use Ant+ through a laptop dongle and don’t think I have any other apps etc running but will have to check.

I didn’t even know there was a shortcut to spindown, so thats good to know, but it was via the menu options that it kept failing. Worked first time with the Wahoo app so it does seem like its probably a connection issue. I’ve also ordered a USB-C adapter so I can use the Ant+ dongle on my new laptop as well, so will see if that helps or not.

Appreciate the advice.

Just to update this, I ran a session today with ONLY the TR app on my laptop and didnt have my Wahoo Elemnt or any other phone apps running.

End result was zero spikes until a few mins before the end when I had 1 very brief but severe spike during a cooldown. It seems like it may have been interference from my head unit that caused the issues so good that it sems to be resiolved. I was getting worried the Kickr might have been on the way out!


:arrow_up:This. I had the exact same problem a few months back, and it was always caused by another device ‘grabbing’ control of the Kickr shortly. Headset, computer running Zwift, GF’s iPhone still running Zwift, you name it.


Same, although its been 4 years now I clearly remember Zwift being connected to Kickr as power meter, and every once in awhile mid-ride Zwift would switch to controlling the Kickr and start fighting with TR app. Stop riding, check connections, and switch Zwift back to Kickr as power meter.

The other issue I had was shadows interfering with the Kickr 2017 optical sensor, which I solved by putting a black Wahoo mat on the shiny concrete garage floor.