Road bike - Crank arm length
08-22-14, 05:26 AM
#2
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Traditional fit rules tie crank length to femur length, but there isn't a lot of empirical evidence to support that. Most riders can be comfortable on a wider range of sizes than the "rules" suggest. The Competitive Cyclist fit calculator will suggest a crank size that is a reasonable starting point, but going up or down a size won't be a problem for most riders.
08-22-14, 09:54 AM
#3
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You doing a piece by piece build up? a bike out of the box will generally have a crank arm length proportional to the size ..
only when you get into the top line components will the choice be more than 170/ 175.
only when you get into the top line components will the choice be more than 170/ 175.
08-22-14, 10:18 AM
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When this topic is discussed here, the replies suggest that most people are insensitive to crank length and a smaller number of people are somewhat to very sensitive.
For those who are sensitive, stated reasons seem to be pedaling style (high cadence/short cranks), leg length, and prior injuries ( that restrict range of motion).
Typical crank lengths for road bikes are 170-175 mm. Mountain bikes used to have longer cranks. Kids bikes have shorter but cheap cranks. You can get short cranks of decent quality by adapting BMX cranks, see Origin 8. Not sure about finding longer cranks.
Crank length is one of the last things I'd worry about.
For those who are sensitive, stated reasons seem to be pedaling style (high cadence/short cranks), leg length, and prior injuries ( that restrict range of motion).
Typical crank lengths for road bikes are 170-175 mm. Mountain bikes used to have longer cranks. Kids bikes have shorter but cheap cranks. You can get short cranks of decent quality by adapting BMX cranks, see Origin 8. Not sure about finding longer cranks.
Crank length is one of the last things I'd worry about.
