When I climb, my watts on Zwift are much less than the watts on my PowerTap
My set up is a Wahoo Kickr Snap and I ride with a wireless PowerTap wheel, so every ride I’m seeing my power output from two different sources. Typically, they’re slightly different - 5 watts, sometimes as much as 10 (my FTP is 240) but mostly consistent, except when I climb. For some reason, the Zwift watts are a solid 25-30 lower. So while my PT says I’m putting out 210 watts, Zwift will say 180-185. So which is right? Well, it feels like the PT is right. I’ve put 4k miles on Zwift this year so it I think I have my perceived exertion dialed into my actual power output. I just did Tour stage 6 up the Alpe and struggled to generate 190 watts on the climb, which shouldn’t be too hard for me. Interestingly, this delta between the two readouts does not occur on flat or rolling courses. Before you ask, I calibrate my PT weekly and run a spindown on Zwift at about the same frequency. My back tire is kept at the proper psi and the firmware for my kickr is up to date. Anyone ever have this experience? Any thoughts as to why I’m getting it?