Yesterday, for the first direct comparison during a turbo session, I got results, which confirmed my suspicions, between my two current powermeters, a Power2max NG-Eco (2 months old) and a PowerTap G3 (recently changed). Unfortunatly, I deleted some of the data. Today, during a ride with intervals of several minutes, I recorded the following averages:
One (or the two?) gave an unexplicated difference during the first lap of the two runs (the relative difference does not depend of the gear ratio and is constant at +/-0.5% during the whole lap). Auto-zero feature was activated on the two power-meters and I stopped pedalling during the laps. I have some guesses about the suspect. More to come.