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Old 09-25-16 | 06:38 AM
  #1996  
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DougG
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Joined: Sep 2003
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From: Rochester Hills, MI

Bikes: 2017 Felt VR5, 2013 Specialized Crosstrail, 2020 Specialized Vado 4.0

Originally Posted by rawly old
Yes, the ratio is about the same. That's the point! The difference is the amount of leverage
one can apply to the smaller chainring is considerably greater.
Try it if you don't believe me.
Think of the crank arm as a lever & the outside edge of the chainring as the fulcrum. The larger
the chainring, the less leverage the crank has against it. It's basic physics.
Hmm... I'd have to refresh myself on my old mechanical engineering classes, but I think that the increased leverage at the crank is offset by the decreased leverage that the smaller-diameter 11-tooth cog applies to the rear wheel vs. the 18-tooth cog (i.e., the leverage that the chain exerts on the gear). In the end, all that matters is the overall gear ratio.
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