It actually is all about physics, irrespective of whichever power device you are talking about. And the effect of riding in bunches would only be relevant if you mounted the ibike at the top of your helmet or wherever you could where it would not feel the difference in wind speed. Sensibly placed on your handlebar, it will not be less accurate in a bunch. amen. On the bars the wind speed will be less since you're drafting and therefore needing less power to keep up... I-bike should reflect this. Come on,.......this is drafting 101, first year cycling. Or have power meters suddenly changed Bernoulli's theorems as well..... **** you never know hey cos Heavier carbon bars can suddenly make a bike lighter at the scales too... saw it myself so it must be true.. If only it were that simple ... "Drafting I did one ride with two other riders, where I spent about 40% of the time in a draft. It was apparent during the ride that the iBike was underreporting my power output in the draft by about 40-50 watts. The pressure port should have accounted for the change in wind resistance, so why the inaccurate reading? My guess is that the iBike sits in the sweet spot of the draft, right at butt level of the rider in front. Most of my body is catching more wind than the iBike, so I'm doing my work than it thinks I am, hence the low wattage. The overall wattage for that ride was 8% too low. I got in touch with John Hamman of iBike and he confirmed this anomaly. He told me that it performs more accurately in a big pack, where the draft is bigger and more consistent. A couple of reports from message boards back up that assertion"
