here's the best example i can find from the four rides i've now done with this meter.
similar time of day (which is critical for me b/c my medications will cause heart rate to be off by about 15% compared to "effort"), similar weather (63f, 44%, 8mph WSW for one, 62f, 36%, 8mph W for the other). heart rate within a few BPM. one says 271w, the other 219w! a HUGE difference. power meter was zeroed before the ride on the right, not before the ride on the left.
for grins, here's what bikecalculator says it should take to do it at 17.1mph, eerily close to the 219w average power of that segment. my guess is that the data from the ride on the left is just wrong, and that the zero offset was WAY OFF at that point in time? all references i can find to this subject for this meter say that the differences are very small, like a few percent at most, but this is 24% higher!
