As you know, the Speed Sensor is really useful on MTB twisty single track trails. It provides accurate distance. The GPS distance (and therefore speed) is often up to 10% too low. You can easily lose 4-5 miles over a 50 mile ride using GPS for distance!
So clearly, we can't count on the auto-calibration to work on one of these rides... since that uses GPS, which can be 10% too low in that use case.
So, when I get a new speed sensor I ride on a clear/straight section of trail or road, and that sets it up accurately.
Many in this forum suggest the speed sensor continually auto-calibrates based on GPS. Wrong. If so, after a couple miles on single-track, the calibration would be bad, based on bad GPS distances on those twisty single track trails. And I don't see that at all. My speed sensor constantly gives me accurate distance, that is 6-10% more than the GPS track.
My question is: can we tell the Garmin computer to re-calibrate a new wheel or tire automatically? If we know we'll be on a nice clear/straight section of trail or road for the next mile or two?
I know I can manually set the tire circumference, but it would be so much easier to tap a button on the Garmin to re-calibrate. I just can't find that option.
