crank length
apart from helping with bike fit is there any other advantage to longer or shorter crank lengths, would shorter cranks produce more power/speed & therefore longer cranks less power but make hills that bit easier. sorry if this is a bit dull but it is getting late

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You can spin quicker with shorter cranks, but will have ever so slightly less torque for the hills. If you are having a bike fitting session they should be able to advise you your "ideal" crank length.Dolan Preffisio
2010 Cube Agree SL0 -
Lots of stuff on the Internet and in print on crank length.
There are some excellent cranksets on the market that allow the user to switch between 170/172.5/175.0 -
I've done a ton of reading research into this just recently, including Steve Hoggs website has a very detailed explanation, however I still come out the other end thinking WTF????
What I gather is that shorter cranks will help with better cadence, whilst longer cranks give more power on the downstroke. However I have just brought a crank which is 2.5mm shorter than the one I have on my bike. Can it really be that different? At my level of riding (250-300 a month, just fun / training no racing) will I even notice?
Many people advocate proportional crank length - if I follow that I end up with a crank of 180mm!!!
Good luck finding out the answer, I'll be checking back to see if someone can finely shine a clear and sensible light on the subject!!!Some people are like slinkies - not much use for anything, but they bring a smile to your face when you push them down the stairs.
http://knownothingbozoandhisbike.blogspot.com/0 -
For road cycling, the question should probably be 'is there a benefit to longer cranks - and what is that benefit'. (with your question being applicable more to track cycling).
I think some of the answer comes down to understanding what might be advantageous for a pro (with massive flexibility, huge power, good biomechanics) isn't necessarily advantageous for a mere mortal.0 -
I've just swapped from 175 to 172.5 mm on the good bike (only because I was offered a set of Red cranks at £280 below RRP), the trainer/commuter is still 175 and I can see/feel:
No difference whatsoever re crank length and related performance.
But that's just me - please don't shout at me if you feel different.0 -
I've never been able to tell the difference between 172.5's and 175's either, I reckon I might be able to between 165's and 180's but never tried either. Basically don't worry much about it, 172.5 is the usual 'one size fits most' spec for road bikes, unless you're a dwarf or a giant I wouldn't worry about changing.0
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No I'll not be losing any sleep over it,
I was just thinking if there was any advantage between the sizes, but like tremayne says to a pro there might well be a difference, but to the average masher, if you can tell the difference between 2mm then your probably a better rider than me, but then that wouldn't be difficult either :roll:
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I just posted an exact thread and was advised to google 'crank arm lengths'. There is an extraordinary amount of info. But it all boils down to so little, its not worth worrying about as the differences i'e 2.5 mm from 172.5's and 175's is so nominal and by changning gear you change the torque setting which is equivalent to a different crank arm length. If your knees suffer as a result of crank arm length change, you need to stretch more ! was the basic response, to get the knee to assist in the rotation.seanoconn - gruagach craic!0
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pinarello001 wrote:. But it all boils down to so little, its not worth worrying about as the differences i'e 2.5 mm from 172.5's and 175's is so nominal and .
It is worth worrying about if you are serious about your cycling, in an aspiring amateur racer kind of way. You can get cranks from 130mm to 185mm or thereabouts.
You can do the sums, but a lot comes down to personal preference. You buy (or borrow) and try. Or you obtain a crankset where crank length is adjustable.0