power stroke interpretation and callibration

[kurt]

Hello,

I have 2 questions regarding a ride that I did today (19/01)

1) around km 34-36 you will see that I had a descend of 2,5 km. My power was zero. Nevertheless I have a wasted watt of 5W and a distribution of 30% - 70%. How is this possible?

2) I never remove the powerpod from my bike. It is very well mounted on my bike. But every time I see a difference in my average speed and the average wind speed. If I do a check calibration my power values change (for mine interpretation) significantly. Can you advise me which are more correct? (I have added both files)

Many thanks

Kurt

[Velocomp]

1) Even when not pedaling, you are still accelerating a bit, both front to back and side to side. Since these accelerations are not the result of pedaling, the PowerStroke numbers are meaningless in this section.

2) It looks like you used Isaac to adjust your file. It is not proper to use "Check Calibration" or "Analyze Route" over long distances, routes that are not truly out and back, or times, because it is entirely likely that wind conditions change otherwise. I can't tell if your unit is miscalibrated or not, but the route you used is inappropriate for Check Calibration.

[kurt]

Hello,

I did 2 tests today. 2 out and back rides
Below you find the values:

CdA Crr Cm
0,3787 0,00539 1,02

Aero Wind Scaling CdA Fric Riding tilt Crr
original 1,1 2,904 0,379 5,18 0,0 0,0054
test 1 0,887 2,342 0,379 11,908 -0,7 0,0054
test 2 0,876 2,314 0,379 10,947 -0,6 0,0054

I have also added the ibr-files. Which values do you think are the best?

Many thanks

kurt

[Velocomp]

Both files look fine and both have nearly identical wind scaling factors.

[kurt]

ok,

So I think I have a good calibration.

My powerpod is installed in a good manner and never leaves my bike. After how many times I should do a new calibration?

Thanks

Kurt

[Velocomp]

It should maintain calibration indefinitely.