Originally Posted by
Wilfred Laurier
Gas is consumed at some point along the production of the bicycle and consumed to supply the cyclist with his needs to ride the bicycle. So the gas consumed is not zero, but is approaching zero.
By that logic, you would need to factor in the production costs of automobiles when quoting their MPGs. When people speak about their car's gas mileage, they are referring to how much fuel it consumes from driving it not from all phases of its production.