Zwift Power & gradient bug/issue (Wahoo Kicker Core)

Hi, after the recent update i noticed there is serious issue on power & gradient lag.

Day 1 Route : Watopia-Jungle Circuit
the gradient resistance on my trainer didn’t match with zwift on certain section, flat/downhill feel like uphill & 4-5% gradient feel like lower gradient (1%) etc. (overall still rideable)

Day 2 & 3 Route : Watopia - Tempus fugit
The gradient issue is unnoticeable (almost flat) but the power lag issue is quite obvious on the sprint section.
The First lap was fine,2nd lap was a nightmare as zwift only detected my sprint power after 4-5 Sec.
(Tested 2 days, same issue happened on 2nd lap-Sprint section which is nearly after an hour ride)

Day 4 Route : Makuri Island - Suki’s Playground (Today)
Today ride are really unenjoyable, the gradient and power lag issues still remain and are noticeable during the whole ride.

1st the whole climbing section has gradient lag issue, resistance feels strong on gradient decrease/resistance is weaker on gradient increase.

2nd after finishing the route and entering the Village sprint section, same old issue on the sprint section.
Sprint power only appears after 4-5 sec (almost mid of the section).
To make sure it’s a bug/issue, I did a short sprint section on Wahoo app, there is no issue on the power meter and also another short ride on zwift - village sprint section (same issue happened again).

Device connected : Iphone 11
Connect Method : Bluetooth
Trainer : Kicker Core (upgraded to Latest firmware)
Zwift-Trainer difficulty : Max
Trainer Calibration : has been done on Zwift & Wahoo App (ever day after issue arise)


The latest firmware was supposed to have resolved the same issue that crept in after the release before this one.

The only solution was to roll back to v1.0.13

This latest release has had the same effect on me as it has you. So I’ve rolled back again to v1.0.13 and this has resolved it, again.

I don’t know what the problem is but this Wahoo/Zwift combination just doesn’t work for me.

1 Like

@Martin_Lowe appreciate for the sharing.

@Tom_Hagler has a post somewhere on here about it if you take a look. Good luck :crossed_fingers:

@Frususx_Yong search for my post " [Wahoo Kickr Core 1.1.1 firmware issues]"

Hi @Tom_Hagler

Have you tried the latest Wahoo upgrade? If so, how did it work for you?

Ya, just saw Tom post after google search.

:+1: just roll back to V 1.0.13,will try on tomorrow.

I’m using 1.1.1 again…and it seems to work with my macbook. I turn bluetooth off, start Zwift, turn bluetooth on, wait until Kickr etc. are connected and start riding…

Thanks Tom. I use Apple TV and you cannot turn Bluetooth off. It’s permanently on.

Do you have to turn the BT off and start again before every session then?

Yes. Before every session I turn of bluetooth and then start Zwift, turn bluetooth on. I have not installed the Apple TV app,but here is something you could try (don’t know if this feature is available on Apple TV): On the device connection screen don’t choose the Apple TV bluetooth, choose “pair with companion app” - and have your Zwift app ready and the Kickr connected to your iphone bluetooth. This worked for me on Mac as well (with latest firmware).

It also happended to me…Im using ipad & Magene Gravat2.

Updated :

  1. After rollback from Ver 1.1.1 to Ver 1.0.13,basically solved the Power & gradient lag issue.
    but Gradient lag issue still appear randomly so yesterday i decided to upgrade back to Ver 1.1.1 to have a try.

  2. After rolldown to Ver 1.0.13,i’m feeling the resistance is slightly softer than Ver 1.1.1. which my performance overall increase about 10%. (Am i the only one?)

  3. The gradient lag issue did appear randomly but only on the transition section like from 6-8% to 9-10%/above. (Still having this issue after upgrade back to Ver 1.1.1)

  4. Tried the method mentioned by Tom (Turn-off Bluetooth and only turn on after enter Zwift) so far the issue still happened randomly.