Same issue for me, Kickr V6, had been working fine for a few months then after the latest update I decided to get Zwift play controllers to use virtual shifting now my power is way higher than power meters I’m using, I’ve since gone back to a Kickr V5 and there is no issue. I hope it’s a software issue and Wahoo/Zwift fix it
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I just did the Big Spin ride on Country to Coastal and tried unsuccessfully to find a workaround (besides the obvious one to just deactivate virtual shifting).
For the first part of the ride I had not connected the Play controllers and used mechanical shifting. As soon as I connected the controllers the oscillation kicked in again:
The oscillations become more prominent, when producing more power:
Here is what this looks like in Strava:
The distance from peak to peak of the wave is about 60W (i.e. an amplitude of 30W), which is more than 25% of the average power here. The period of the oscillation is ~7s, i.e. the frequency is ~0.14 Hz.
I also tried to change the trainer difficulty from 20% to 100%, but that didn’t change anything either.
I think I will deactivate virtual shifting for the time being and only use the Play controllers for steering.
@shooj Do you know if anyone at Zwift is looking into this issue? I can provide more data if needed.
I have the exact same issues. With virtual shifting enabled the power cycles every 3s
and without it’s as smooth as I pedal.
Have there been any developments with this issue? I am using a Kicr Core, old firmware, Play controllers, Windows 11. Everything basically works ok…
I’d be quite keen to upgrade the firmware and switch to virtual shifting. I’ve also seen reports elsewhere that resistance stops for some. So is there a risk I’ll end up with an unusable machine? Should I just stick with a working setup, or take the plunge?!
Hey all - a few things were raised in this thread that I wanted to comment on.
Wahoo added support for both virtual shifting for the KICKR Core and auto spindown in January 2024 in firmware revision 1.3.17. To assume that “virtual shirting prevents autocalibration” is jumping to conclusions, let’s be open to investigations without making this assumption.
@Miro_Wikgren
The zero watts issue affecting macOS users was fixed in Zwift game version 1.58.2. as @SeattleSauve noted already. Would you confirm that issue is resolved for you?
@Umut_YILDIRIM
The wrench icon disappearing from the pairing screen is expected behavior once your trainer is on firmware that supports auto-calibration.
@Bastian_Wegener
Wobbilng at the pedals in the first ~15 seconds after your avatar spawns in a world sounds like the expected feeling when your trainer is determining the physical gear ratio on your bike. During this time, the trainer is reading its flywheel velocity and your pedal cadence, and is calculating the gear ratio of the bicycle, then puts you into a virtual 12th gear, right in the middle of the virtual gear range.
Real Gear Calculation happens one time, when your avatar spawns. Should you shift your front derailleur from small chainring to large, the trainer does not recalculate. Does this sound like the wobbiling feeling you’re describing? If no - please elaborate.
More broadly to everyone in this thread - please elaborate on the issues - there are several being raised, and I want to be clear on what you’re describing here.
- Are you in ERG mode or SIM mode?
- Some of you have mentioned, but what pedal cadence range do you prefer? Is it below 60 rpm? 90? 140?
- If in a SIM free ride - what sort of terrain? Hilly? Flat?
- What size chainring is on your bike, and are you shifting the front derailleur at all?
- Which virtual gear number(s) do you favor?
@Efflon Is Power Smoothing enabled on your Wahoo trainer? See this article on the Wahoo support site for details.
As I wrote the wobbling was after ~100m for the whole ride. Like if you modulate a frequency with a 3-5speriod in addition to your power. This is shown in the The last race I did without virtual shifting and everything was ok. Will try with virtual shifting again.
The power smoothing is just how it’s presented on screen. As the Wahoo article says, it doesn’t change what is captured by the app from the trainer. The reported trainer problem sounds like an issue with actual power fluctuations from the trainer.
For that matter Zwift can also present actual or “smoother” power data on screen, but again no impact on the actual power reported by the trainer and captured by Zwift.
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I have a 3 week old Kickr Core and having the same issue. It seemed to have started with the March Update for me. I have been using virtual shifting, and it happens at any RPM. Last ride I was pedaling at 90rpm around 3.5 wpkg and it would fluctuate to around 2.7 wpkg every few seconds. It doesn’t matter if power smoothing is on or not, same results.
I use the small chainring and spend most of my time on flats between gear 13-15. Same issue at low rpm’s on climbs.
There doesn’t seem to be the same issue in ERG mode. I’ve sent something to Wahoo as well.
Does this oscillation happen when 10hz race mode is switched off?
The reason I ask is that torque (and therefore power) is not consistent through the pedal stroke and follows an almost sinusoidal profile.
It may be the way Zwift is dealing with10 data points every second.
I’m not sure why it would only show up only with virtual shifting, but would be a good AB test to turn off 10hz and report back.
I didn’t even know this setting existed. So I imagine whatever the default setting is, that’s where I’m at. Didn’t have this issue before, so I wouldn’t think this is part of the issue?
It’s in the wahoo app. It’s called race mode.
It used to only work with direct connect but the latest firmware enabled it via Bluetooth.
It’s a great feature to have as it gives your avatar much faster response.
It could be that the virtual shifting algorithm, which uses rpm, isn’t smoothing the 10hz power data.
Best way to check is to isolate it and turn it off to see if you still get the same behaviour.
I’ve got KickR V6 and haven’t noticed any fluctuation issues. But I have had a couple of instances when coasting where my watts wouldn’t drop to zero, which was very annoying when trying to supertuck.
Maybe not on the Kickr Core…
Similar to the 10hz comment.
I find it interesting that it’s a 5s duration.
Could you say what cadence you were doing?
For example if doing 85rpm, you would complete
7 complete pedal revolutions every 5seconds.
Did you get the same experience with 10hz switched off?
Does the core have 10hz mode?
Thanks for looking into this, please find my answers to your questions below:
- Are you in ERG mode or SIM mode?
For me it’s only a problem in SIM mode. ERG mode is working perfectly fine. - Some of you have mentioned, but what pedal cadence range do you prefer? Is it below 60 rpm? 90? 140?
I haven’t tried super low or high cadences, but I’d say it’s very prominent at regular cadences between 80 to 100 rpm. - If in a SIM free ride - what sort of terrain? Hilly? Flat?
The issue is present on all kinds of terrain and most obvious while the power output is constant (e.g. iTT) - What size chainring is on your bike, and are you shifting the front derailleur at all?
50t chainring, no shifting while virtual shifting is active. - Which virtual gear number(s) do you favor?
If I remember correctly, it was mostly in the range from 13-17 with relatively low trainer difficulty.
If needed, I can provide the fit files for some rides I did with virtual shifting, where the issue was pretty obvious.
@Steve_Jukes AFAIK the KICKR Core doesn’t support 10hz race mode.
If your watts did not drop to zero you have extra watts all the time → you should make a (factory) spindown
Thanks Steve, I’ll look into this.
It does read zero at rest and when not pedalling.
However, at high flywheel speeds, if I stopped pedalling, my watts went to zero immediately.
But after a 2 or 3 seconds, I sometimes got a ghost cadence spike and 5 watt power reading which took me out of supertuck. Very annoying when trying to keep speed downhill.
I did a factory reset as requested by wahoo a few weeks ago and also nipped the belt tension up slightly, ive not had this issue since.
Oh, thought the Core was included.
Probably not 10hz causing it then.
I always wondered if it is the first ~15 seconds after I show up in a world or first ~15 seconds after I start pedaling? Considering situation when I join start pen and do nothing for 5 minutes.
On the other hand, for me the virtual shifting on Kickr Core works fine 
.