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Old 12-04-08 | 04:06 PM
  #67  
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Brian Ratliff
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Joined: May 2002
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From: Near Portland, OR

Bikes: Three road bikes. Two track bikes.

Originally Posted by cuski
Brian, not to be nitpicking there, but you forgot an important force in your decomposition - traction. Since we're dealing with a wheel, much like humans movement, friction in this case acts like traction, so you would also have

a1 = (Ff1 + Fgrav1 - Fd1) / m1

since Ff1 = μN where N = m1 * g cos α, you end up with a higher traction for a heavier rider.
Yup.

I simplified because rolling resistance is such a small force (less an order of magnitude) compared to the force required to accelerate 200lbs up to 40 or 50mph against air resistance. So sue me.
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