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Does crank length matter?

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Does crank length matter?

Old 10-11-18, 10:56 AM
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Originally Posted by 1500SLR View Post
There is no evidence to support the fact that crank arm length makes any noticable performance difference. On the other hand different crank arm lengths may suit your knees and legs better. This is really one where "ride what fits you" is the best answer.
IME (40+ years of it), this is true. I'm 6'3", 37" inseam (long legs run in the family) and have settled on 175's, mostly because they work well for my pedaling style (high rpms) and are easy to find. I've tried everything from 160's to 180's on a variety of bikes, both conventional and recumbent and never found a noticeable performance difference. (I'm not riding 'bents any more but settled on 170's there.)

As with anything, ride what ya like and like what ya ride.

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Old 10-11-18, 11:21 AM
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It all matters.

As you ride & age
Your body changes.
pay attention to it.
Cadence & fit changes.
A 1/8 or even a1/16” can make a difference.
Gearing changes too.

Folks 5’9”, with 30” stand over ...... will have
many different fit specs.
Make small adjustments till you find yours.
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Old 10-11-18, 11:31 AM
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Originally Posted by phtomita View Post
I was looking the new 105 R7000 specs and they added a 160 mm crankset.
Currently I have a 5800 165 mm and don't have any issue, but thinking on getting the shorter one since it means I bend a tiny bit less the knees while spinning.

There you define your needs , you want high cadence spinning, I don't..
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Old 10-11-18, 11:51 AM
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I have a history of sensitive knees. I get some sort of biofeedback that makes me ride lower gears and higher cadences ”automatically” on bikes with shorter cranks, which is more likely to keep my knees content.
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Old 10-11-18, 11:54 AM
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According to that formula, my "number" is: 153.

I've used cranks from 155mm to 175mm. My own preference and best comfort is in the 155-165mm range. Current bike is at 170mm.

Have been eyeing the Thorn Short Triple crankset (which goes down as low as 150mm for the arms).

Haven't measured efficiency and power differences.
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Old 10-11-18, 11:11 PM
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Here is a pretty good article/discussion about crank length I read a couple weeks ago that talks about all the formulas and the positives and negatives of each one-
Steve Hoggs - Crank Fitting, Which One?

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