AeroPod, PowerPod and Newton

After a few rides, I tend to hit the check calibration (not rides conform to an out/back, but can be 10-15 miles one way.

For the most part wind calibration changes are typically in the noise. However I have seen 30% increases in the friction coefficient. On rare occasions I find that a rim brake might be rubbing a bit and adjusting that is corrected. I also have one rear wheel that seems to have a little rub in the freewheel - if I hang the bike up and move the pedals in reverse, the wheel can start to move from a bit of friction.

I have not moved or knocked the PP, but there have been a few times when the tilt goes from a small value to 2 or 3%. I just don't find that the PP has been hit that could change the angle of attack.

So the check calibration is useful for minor bike maintenance. But if I find nothing amiss, why does there sometimes seem to be adjustments that are "significant?"

Friction changes are the result of your tilt measurement changing. I do understand that you are not moving PP, but tilt can change simply as a result of walking the bike after a ride, or moving the wheel while hanging up the bike.

When I finish a ride, I click my device's button 5 times. The light goes solid green/yellow/red then off. This turns off the device. Any movement of the bike when the device is off won't affect tilt adjustment.

Also, I recommend you take a look at "Analyze Route". This is not as invasive as the Check Calibration control.

Yep - I do that after every ride - analyze route. Almost all my recent rides have been in low wind conditions, so I really do not expect a wind scaling impact. But I have seen friction go from around 11 up to 30.

I also recognize very much that excessive motion after the fact can influence any data analysis.

I stop the bike and with vey little movement hit the button 5 times - it does not linger in lala land before I shut it down. This is a matter of a minute or two at the most - without holding the bike up in the air or anything like that.

I do find that the times I recalibrated, the resulting values are quite consistent - it is only after a lengthy O/B that any calibration parameters see shifts. I am tending to ignore them.