The pedals and crank arms must not be touching anything. It is also important to avoid carrying out the calibration in situations involving significant changes in temperature, for example if you perform the calibration shortly after taking the bike into the outdoor air on a cold day (around 0°C) if it was previously stored indoors (around 20°C). As such, calibration must be performed indoors before going outside, or else after the bike has been outside for some time (thus when all components of the Power meter have reached ambient temperature).
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