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Old 12-17-09 | 05:02 PM
  #13  
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Bontrager
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Joined: Dec 2004
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From: Boulder, CO

Bikes: Road, MTB, Folding, Commuting bikes...

Originally Posted by gr@sshopper
Ok, stupid question. Can you think of a crank arm as a lever? The bottom bracket is the fulcrum, the chain ring would be the load. Moving the load closer to the fulcrum means less force but movement through a longer distance.
Yes. Torque = Force x distance x cos(theta).

Probably easiest to calculate when the crank arms are at 3 and 9 o'clock.
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