Apparently one gallon of american petrol contains about 31000 kcal.
http://auto.howstuffworks.com/question527.htm
that about 8200kcal per liter. I've read that a cyclist moving at 19mph burns about 800kcal per hour. that means 1000kcal gets him 24miles, or about 196miles per liter (313km)
I think that number is a touch off.
I'll eat 8200kcal in two days. There's no way i can ride 1000+km at my regular pace on that much "fuel" (and for people like Mackha (
) who will challenge me on this, I understand that a lot of energy goes to just keeping the body alive, and NOT riding a bike!).
http://www.caloriesperhour.com/index_burn.php
The discrepancy comes in on how hard you pedal at speeds of 10mph you consume far fewer calories.
It takes less energy to bicycle one mile than it takes to walk a mile. In fact, a bicycle can be up to 5 times more efficient than walking. If we compare the amount of calories burned in bicycling to the number of calories an automobile burns, the difference is astounding. One hundred calories can power a cyclist for three miles, but it would only power a car 280 feet (85 meters)!
http://www.exploratorium.edu/cycling/humanpower1.html