@Egika hey, I didn’t try. The sensor is correctly calibrated to the wheel size.
If it was a calibration issue, the speed would be consistently wrong, not inconsistently wrong, eg if I was going 25km/h, and the size was set too big, it would show 30km/h, instead of 25 25 25 7 5 3 7 12 25 25 25.
Edit: it makes me think of the power meter issue reported on the main firmware update thread, with dropouts: if the Bluetooth connection to the sensor dropped, and the watch wasn’t receiving the correct revolution data form it, the speed would be incorrect.