Rule of thumb is your power output (in Wats) x time = energy output in Joules. The body is horrificaly ineficient so 1J = 1cal (1kJ=1Cal, 295Cal=Snickers bar), depsite the actual number being about 3.5 (i.e. the body needs 3.5 Calories to do 1 Calorie of work.
Power in Wats = body weight x (FTW power/weight ratio)
FTP power/weight ratio
~1 unfit, I’m only here for the cake
~2 middling to average group ride on MTB’s,
~3 quick roadie club run, (Cat 4 race)
~4 roadie who actualy races (Cat2 races)
~5 pro
6+ Bradley Wiggins called, there’s been a mix up with your results as his seem to show a midle aged cake eating mountainbiker.
7+ Alberto called, he wan’t the name of your butcher?
So calories per hour = 3.6* (power/weight) * weight in kg
So for me = 3.6 * 2.6 * 94 = 880Calories/hour
But that’s average, over the time I’m actualy pedaling. On a road ride 10-20% of the time is probably coasting (or at least not pedaling as hard as possible) downhill, so nearer 600-700Calories.