Mountain Biking - Crank Arm Length

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View Full Version : Crank Arm Length


brooklyn
06-13-05, 09:38 AM
Is there a noticable difference between a 170mm and 175mm crank arm lenth? If so how will this change my riding?


darkmother
06-13-05, 10:00 AM
You can feel the difference, especially when you first change over. All in all, it is a pretty small change-only 3% difference. It will give you slightly more torque, but be a little bit tougher to spin fast. Personally, I ride both 170 and 175 on different bikes, and there is not that much functional difference.

Habu2112
06-13-05, 10:19 AM
Mother is right. A shorter crank arm is easier to spin. A longer crank gives more torque. I have a 172.5 on my road and a 175 on my mountain bike. Also, most smaller frame bikes have shorter cranks, most larger frame bikes have longer cranks (from the factory).