No resistance on Kickr Core after completing a workout

Hi All!

Occasionally, after completing a workout in Zwift, I like to continue the ride on course. After I ‘ok’ out of the workout summary, I remain on course but I have no resistance from my Kickr Core. This doesn’t happen every time, but seemingly only sometimes. It is as if the trainer switches out of Erg, but somehow is not getting resistance information from Zwift. I have tried un-pairing and re-pairing the trainer, and it doesn’t help, I also sometimes then run into that weird pairing loop bug that I have seen posted here. At one point doing this, the trainers resistance went so high that I couldn’t turn over the cranks, and un-pairing/re-pairing just removed all resistance again.

No, nothing else is pairing with my kickr, i just have the Zwift companion running on my phone (I use ATV for zwift). Obviously, my kickr climb isn’t working when this happens either.

Do you have the latest firmware for your Kickr?

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Yes, latest firmware. Rode yesterday, finished a workout and didn’t have the problem, although when I paused the workout during the warmup to grab a sweatband, which I had forgotten, ERG mode didn’t seem to be working and I was only putting out about half the wattage as was required. Had to quit the workout, restart zwift, un- and re-plug in the kickr core, and it finally worked again. I just wish all this equipment wasn’t so buggy, my Kickr Climb only works about half of the time.

Hi @DRES welcome to the Zwift forums.

I’m looking at a couple of your recent ride session logs on our server. There’s a heart rate monitor registered on the server ID’ed as “Dan’s HR.” What make / model is it?

The odd thing is that this HR monitor is connecting to the game as a run speed data source at the same time as the Kickr is connected as a bike speed source. This conflict isn’t good.

Also, do you have another trainer, specifically rollers? The Kickr isn’t registered as the connected trainer.

I’d like to know more about this heart rate monitor, and if you’re using it as a Bluetooth bridge device to connect your sensors to the game.

I stopped using workouts a couple of years ago because it would take days for my KiKr Snap to return to normal mode when free-riding. I don’t do a lot of training workouts, but, I’d like to be able to do some once in awhile, so, if there’s a solution to this I also would like to know.


Thanks for looking into this. My setup is:
Kickr Core 2018
Kickr climb
4iiii Viiiiva HR monitor
Wahoo cadence sensor

The Viiiiva is working as a BT bridge for the cadence, as I am using an appleTV 4k and dont have enough bt channels.

I don’t have any other bike trainers, no rollers, nothing. Not sure why they HR sensor is connecting as a run sensor, I don’t run on zwift.

I usually run zwift companion on my phone when riding, and I also have BT headphones connected to my phone for music.


Thanks for the additional details. I suspected it might have been a Viiiiva HR monitor, which is known to behave oddly if you change its Bluetooth ID name.

Please have a look at the Heart Rate Monitor pairing page, specifically the part about the 4iiii’s default name.

You might also consider flashing new firmware to the HRM for good measure. There was a recent thread where another Viiiiva owner’s issues were resolved with the above two steps.

I looked into the firmware flash but the HRM was apparently up to date.

I checked this morning and yes, the Viiiiva is running the latest firmware.

I am not sure what the Viiiiva’s default name was when I first installed it, so I cannot reset the name back to factory unless there is a way of fully resetting the HRM, which doesn’t seem to be mentioned in the HRM manual.

Two training rides in a row now the ERG mode seems to be switching back to controlled resistance after the ride, so maybe it seems to be fixed. I did notice a prompt from the ATV the other day that my HRM had been disconnected and needed to be re-paired, not sure if this was something done by one of you or not…

The default name for the HRM seems to be Viiiiva.

Glad to hear you’ve made progress. Fingers crossed that it continues working well! Regarding the prompt on the ATV - we haven’t done anything from the Zwift end.

You may have contact 4iiii for assistance on that one, but maybe try Marks’ suggestion first?