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Wind shows always behind me on a circle ride
Posted: Sat Apr 11, 2020 7:05 pm
by djetal
I recently had my bike serviced and they routed a shift cable so that it is about 3/4" in front of the lower left side of my Powerpod 2. On my first ride, I didn't see anything that concerned me. On my second ride, over a similar route, it appears to me in Isaac that the PowerPod read a tailwind for the entire ride when in fact I was riding into the wind for the first hour. For both rides, the first half of the ride was into the wind, the second half was with a tailwind. For the first ride, the wind was about 4 mph. For the second ride, it was about 13 mph. Also, I didn't remove the PowerPod between the rides, but the screw does not tighten it completely tight. I looked occasionally during the ride and it seemed parallel to the ground throughout. Am I interpreting the ride files correctly, and would the cable obstruction be responsible for the problem? I'm not a sophisticated rider at all, and I may be not understanding my ride files.
Re: Wind shows always behind me on a circle ride
Posted: Sun Apr 12, 2020 8:18 am
by Velocomp
I think your are OK.
Your 4/6 ride has a large headwind on the out portion, with a large tailwind on the return section. Wind readings are pretty symmetrical, which means that the wind sensor is properly calibrated. I checked your measurements with
http://www.aerocoach.com.au/power-from-speed/ and they seem correct.
Your 4/11 rides shows places of significant tailwind. Were you riding in a group, or was it raining? Either condition would cause apparent tail winds.
Re: Wind shows always behind me on a circle ride
Posted: Mon Apr 13, 2020 1:33 pm
by djetal
I was alone on the ride. No drafting. No rain.
I would have expected at least 75% headwind on the out portion (part of the out portion was perpendicular to the wind) and 80% plus tailwind on the return portion.
The 4/6 ride was as I expected. It's the 4/11 that has me puzzled.
Re: Wind shows always behind me on a circle ride
Posted: Mon Apr 13, 2020 5:41 pm
by Velocomp
Please check your wind port to make sure there is nothing in it.
I don't have any explanation for the 4/11 ride file. After your next ride please post it.