They were all head winds–or so it seemed. Actually, I know I had a good tail wind where I rode along at 27 mph for a good distance. Overall, my average speed was 15.2 versus 16.2 from my 12/15/2006 ride of the same route. My average heart rate was also 10 BMP higher than the December ride [149 BMP versus 139 BMP]. I do not know if that is conditioning, the wind, or some other factor. I also made this ride on my Trek 5200 rather than my normal Project One ride. It was FUN!