Cold bad. Warm good.
This clearly shows the effect of temperature. David Wilson (one of the authors of Bicycling Science) sent me a quote by Jim Papadopoulos from the 3rd edition:
"Preliminary PowerTap measurements on the road and on a home ‘wind’ trainer have suggested significant effects on tire rolling resistance of temperature (with Crr dropping roughly one percent for each degree Celsius of temperature rise) and speed (with Crr doubling when wind-trainer speed reaches 5 m/s)."
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The point I was making......some tires are worse than others. Some lose much much more than 1% per degree C. If yahoos like me know which tires are less slow in the cold, I suspect the professional teams do as well.
I wonder if the Pros still buy FMB and Ducast tubulars and black out the name.