200W (~3 W/kg) has been Zone 2 for me (HR <130) for at least a year. 263W is my current FTP detected by Zwift (I’ve never done an FTP test), and this was auto-updated in Zwift on 1/16/22. My equipment:
Kickr Gen 1 (2014)–new firmware last released 2017
Stages SS PM (2021)–latest firmware
Tickr HRM (2021)–latest firmware
Zwift on Macbook Air (2013; Mojave)–Zwift latest build on 1/21/22
Beginning on 1/22/22, I couldn’t even get to 200W without 150-160 HR. Since this time, Zwift seems as if it registers about 40-50W lower than my effort. Previously, I could do 205W forever with HR < 130. I can barely get to 205W now. Nothing has changed in my fitness; no COVID.
The only changes I remember are (1) 1/21/22 Zwift update and (2) 1/22/22 Stages PM battery died. I replaced the PM battery, and nothing changed—every ride seems so much more difficult (again, 40-50W or so).
Did the Zwift update do it to this old Kickr? I’ve also noticed that my PM Bluetooth signal is only 1 bar when paired to laptop or phone. When I place the phone touching the crank, it goes to 6 bars. I don’t think the BT signal is dropping, but could the weakness be the issue? Still, even when I use the Kickr as the power meter, I still get the much increased difficulty.
I tried bypassing Zwift and used the Wahoo app with Kickr power meter. I still struggled to bring the trainer to 200W (much less sustain it). I then used the Stages app only connected to the Stages PM, and my power seemed normal (yes!). This all leads me to believe it’s the trainer and not Zwift and not the Stages power meter.
I’ve power-cycled everything. I’ve cut off and on Bluetooth on everything. I’ve factory-spun down the Kickr. Still the issue—which is so bad that I get dropped on all my normal group rides, etc.
Anything else you can think of beyond dropping $$$ on a new Kickr Core?
I tried bypassing Zwift and used the Wahoo app with Kickr power meter. I still struggled to bring the trainer to 200W (much less sustain it). I then used the Stages app only connected to the Stages PM, and my power seemed normal (yes!). This all leads me to believe it’s the trainer and not Zwift and not the Stages power meter.
When you set the Kickr to 200 watts via the Wahoo app, what is the Stages registering (connect it to a watch/head unit or another phone/tablet)? Have you done a calibration spin down on the Kickr recently?
I tried bypassing Zwift and used the Wahoo app with Kickr power meter. I still struggled to bring the trainer to 200W (much less sustain it). I then used the Stages app only connected to the Stages PM, and my power seemed normal (yes!). This all leads me to believe it’s the trainer and not Zwift and not the Stages power meter.
When you set the Kickr to 200 watts via the Wahoo app, what is the Stages registering (connect it to a watch/head unit or another phone/tablet)? Have you done a calibration spin down on the Kickr recently?
Exactly… see where the disparity is.
Need a separate head unit or recording device though.
record both the kickr and stages BLE channels to Zwift and then use your garmin/wahoo computer to record the same via ANT+
Use Zwiftpower.com Analysis to compare.
Remember you are measuring power at two separate places (Stages at the crank arm) & (Kickr at the hub) so they won’t be 1:1 due to loss of power in the drivetrain.
So you’ve got zwift reading the power from the stages, and not the kickr? Which is good, and how I’ve my neo/quarq setup. But I know occasionally things get changed on the pairing screen without me noticing and that leads to a situation like yours. In my case it’s when it pairs to the other Neo if my wife is riding at the same time.
Most phones can be used as headunits for this - plenty of free ant+ and blutooth cycling apps to download.