Originally Posted by DrIsotope

If you go off of ANY of those guesstimator websites to plan caloric intake based off of exercise output, you're gonna gain weight. I'm over 200lbs, and my BMR is ~82Kcal/hr. So on a 2-hour ride at my typical pace, I will burn ~165Kcal being a person, and ~1,300Kcal from moving the bike.

All three of my rides this week have been metric centuries over different routes, at different speeds. But roughly the same lengths.

63.0 miles / 1,572ft = 2,014kJ
63.1 miles / 2,994ft = 2,145kJ
64.7 miles / 2,000ft = 2,135kJ

Notice a pattern there?

I have done 4,000Kcal on rides before, though. Back in April I did 108 miles @ 19mph. 3,984Kcal.