Today i start my training plans for the upcoming race year. Yesterday, I compared the virtual power, against my Power2Max and it looks like the virtual power is somewhere around 30 watts off. I would just use power match, but i will switch between my road bike and my TT bike so i want to keep the value consistent on both bikes so virtual power makes sense for me to use for my indoor training. (Note that my TT bike has a left only stages PM).
With all of that said, i plan on doing the ramp test using the Kickr’s virtual power, but also track the ride on my garmin with the P2M, and then manually calculate my FTP value with that PM to use for my outdoor riding, and then use the virtual power for all indoor training regardless of bike.
Does this logic make sense, is there anything i am missing? Is it normal for virtual power to be that far off? Note that what i was seeing yesterday was like a 30 watt difference, i.e. steady 200 watts with virtual power was resulting in about 170 on the P2M. When i jumped up to say 240 watts that same 30 watt difference was still there so the gap seems to be consistent which i think makes sense.