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  1. #1
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    crank lenght: road avg 170mm, mountain avg 175mm. Why?

    Seems like the average mountain crank is 175mm and the average road crank is 170mm. Is that correct or am I just confused. If that is the case then WHY is that the case? I'm not trying to start a debate about which is better for who etc. I'm just wondering if there's some sort of historical fact that brought this about.

  2. #2
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    Cadences are faster on the road and shorter cranks allow for better spin. Also ground clearance since road bikes sit lower to the ground, shorter cranks allow you to pedal through turns. Tight ratio cassettes make it easy to keep your cadence right in the sweet spot.

    Mountain bikes tend to involve some mashing up hills and slower cadences to larger cranks allow for a better torque advantage. Cassettes being wider spaced only add to this.

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