Bluetooth improvements for controllable trainers & treadmills [January 2022]

I can’t get on with a neo and a MacBook Pro. never had problems in three years until they started playing around with these ‘bluetooth improvements’.


For the past week or so Zwift no longer recieves both bluetooth signals for my HRM and cadence sensor when transmitted from the HRM.

AppleTV 4K on direct wire high speed ethernet connection
Wahoo Kickr v2 (2015)
4iiii Viiiiva HRM
Wahoo cadence sensor
Wahoo TickrX HRM/cadence
Fresh batteries in all

Since the Apple TV only has 2 open bluetooth connections available, for years I have been using the Viiiiva HRM to transmit both heart rate and cadence over a single bluetooth connection. It has been issue free. It stopped working with the latest update, so I bought a new Wahoo TickrX to try and that also did not work.

I can connect the HRM separately and it works fine for heart rate only, and same for cadence only. However, as of last week the HRM can no longer transmit both heart rate and cadence simultaneously to the AppleTV.

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Hi @shooj
Any chance you or one of the Zwift team can clarify exactly what the Bluetooth changes are or do?
My kickr 17 is connected to Apple tv4k via Bluetooth and it’s like riding through treacle despite a z1/Z2 ish power number being reported. The flywheel comes to a stop in seconds when in Zwift, yet a ride on the wahoo app will happily see it spin much much longer when coasting.

Can’t work out if it’s bad legs ( can’t make the power) , the trainer is misreading the power or Zwift isn’t playing nicely with it. I couldn’t even stay in the c pace partner pack earlier where I can usually do a couple of hours with the B bot.

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Hi Shuji, we need to understand what these changes are, my observations in the control point are:
Zwift is requesting control of the bike (control point: 0x00) which my application is accepting .
After that, ZWIFT used to send bike simulation parameters (0x11, free riding) or target power (0x05, erg mode), about 1 notification per second.
With the latest update I’m no longer receiving this data, hence the resistance doesn’t change.

Is there a specific setting required for the Fitness Machine Feature characteristic 2ACC of FTMS Service (UUID 1826)?

I assume this impacts many trainers.


Hi all,
I’m still trying to isolate the exact reason, but having intermidant bluetooth connection between my turbo (kickr snap) and cadence (wahoo) and also the wahoo Tickr hr strap. Have had no issues for 18 months with this setup running via Bluetooth to iPad, PC and Mac.
I’m using a workaround at the moment using ANT+, but have to use my android mobile to run Zwift as it’s the only device that can receive ant+ I have right now.
Further testing today using a bluetooth dongle on a lead seemed to eliminate the issue, albeit needing the dongle sitting very close to the turbo, whereas before the laptop could sit and use it’s built in sensor from about 4 metres away.
I’ll keep in touch with the thread, as the only thing that’s changed for me is the latest update, but could be a coincidental issue with the turbo and HR strap.

Hrmmm… maybe thats why been having weird issues on ATV recently. Kickr '16 with some “questionable” resistance changes… Today on TdZ stage 2, standard ride, climbing up to the turn off for the Innsbruck climb, sudden had a massive increase in resistance and took “ages” to back off. Another day, free riding on watiopia, lost all resistance changes

Mines been killing me!
A 1 hour ride with an avg wattage on zwift of sub 150w has me feeling more tired than a 3 hour club ride outdoors with a +200 avg

@shooj hi, can you get any further info for us on this?

Seems to be an awful lot of kickr/kickr bike users especially with Apple TV set ups that are having issues with trainer control…… is it your changes doing it ?

Was having terrible issues with resistance being off, sometimes nearly impossible to pedal on a descent with my KickrBike. Stage 2 on Tour Zwift up the Alps was ridiculous, every time the gradient went down in a corner I could hardly push the pedals over. I rolled backed firmware on the bike from 1.25 to 1.22 and just completed Tour Zwift stage 3 with no problems. I did this after reading thread about folks with Kickr Core rolling back the firmware to fix a similar bug.
I’m using an iPad Pro and Bluetooth.

I was using an older kickr 17 and had done so since Dec 17 which hadn’t had a firmware update or one to roll back for ages, and the last week and half were horrendous, I gave up today and threw a blanket of change at it.

Deleted zwift from Apple TV and reinstalled
Moved my headwind fan a bit further from the bike
Bought a new kickr v5 ( but didn’t update the firmware)

I did a 30km test ride using c cadence as a benchmark, quickly found myself riding away from the pacer and doing a decent 20min effort and then an effort on a climb. Zwift was finally back as expected. !! A marked change from me being a B class rider who often sits with the B pacer for a 2hour block being dropped by the C pacer after 10 mins last week because I couldn’t hold the effort! 120w felt like 320w !