Depends on the time of the year for me. Average lets say 1.5. More in the winter and early season. I do a small number or road races each year that might top out at 4 hrs. Having said that, I probably average one ~5-7 hr ride per month year round. Not sure why, other than than my body feels really good when I'm on high volume. Also often it feels really tired... But sometimes great! It feels good to be 5+ hrs into a ride with respectable avg power and feel like you have plenty of gas in the tank and are ready to hammer every hill and lift the pace into VO2 zone at will. I also like to feel really tan and skinny.
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"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste