Well, most adults around 150# or more, will burn about 900 calories going 17-18mph in one hour of riding.
The average beers usually have about 150-200 calories depending on whether it's michelob or a heavier ale.
So, if you are riding fairly vigorously at 18mph, it should take you at most...
About 15 minutes. Less if you are really pushing hard.
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President, OCP
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