Author Topic: Crank arm length  (Read 366 times)

Online aliasdck

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Crank arm length
« on: November 20, 2019, 05:58:58 AM »
My cranks are old and heavy. They are 160mm FSA crankset with 19mm spindle and weigh like 1276g (2.81 lbs)! according to the parts lists here.


I've been thinking about replacing them with something newer and lighter. Any advice on how to choose crank arm length? I'm thinking of sticking with 160mm because this is what I'm used to.. I am beginning to work on pedal tricks nowadays - like pedal to pedal time machines and other rear wheel pedal tricks - so I do want to put some thought into this before spending any money.


What reasons do people have for going with shorter arms? Obviously on small frames clearance becomes a problem, so short arms would make sense there but this isn't an issue for me as my bike is pretty long with lots of room. Short arms are lighter which would satisfy weight weenies.... But are there any other reasons to consider shorter arms? Or should I just stick with 160mm since I've been riding that length now for many years?


Any insight is appreciated, thanks.
« Last Edit: November 20, 2019, 06:28:55 AM by aliasdck »

Offline Revig

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Re: Crank arm length
« Reply #1 on: November 20, 2019, 12:26:38 PM »

you might want to check on the board with the search fonction

Offline MAYTRICKS

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Re: Crank arm length
« Reply #2 on: November 20, 2019, 06:34:40 PM »
Shorter cranks are both more  out of the way and lighter. I spoke to a rider that does multiple pedal tricks and he shared longer cranks are better for pedal tricks but he has gotten used to shorter ones(125mm)for the benefit of them being more out of the way. I myself settled on 145mm cranks after using 160mm length cranks for years. I'm using a 20T sprocket and also wanted that gear to feel a bit heavier using a shorter crank because I find it's more comfortable to ride standing.
« Last Edit: November 20, 2019, 08:48:37 PM by MAYTRICKS »

Online aliasdck

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Re: Crank arm length
« Reply #3 on: November 20, 2019, 08:13:55 PM »

you might want to check on the board with the search fonction

Thanks, I have been reading through old threads about crank arm lengths already. I'm hoping to get more opinions/views on the effect that different lengths has on pedal tricks. I found some discussion like this but still hoping to see if anyone has anything more to offer.

Shorter cranks are both out of the way and lighter. I spoke to a rider that does multiple pedal tricks and he shared longer cranks are better for pedal tricks but he has gotten used to shorter ones(125mm)for the benefit of them being more out of the way. I myself settled on 145mm cranks after using 160mm length cranks for years. I'm using a 20T sprocket and also wanted that gear to feel a bit heavier using a shorter crank because I find it's more comfortable to ride standing.

Thank you, would be nice to be able to try different lengths but it is expensive. I don't find the 160mm to feel "in the way" or anything so I'll probably end up sticking with that length or something close to it.

Offline DaddyCool

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Re: Crank arm length
« Reply #4 on: November 22, 2019, 10:45:28 PM »
Hi, I am using 165 mm cranks for years. I didn't try shorter, only on other riders' bikes. Too short feels like riding a kids bike (ha!) for me. As long as your chainstay lenght is not below 13" I would say it is enough out of the way with 165 mm. And of course for all pedal tricks (also pedal five or other front wheel stuff) your center of mass will be higher which in theory should make it more difficult to balance.You are working on pedal time machines, don't you? I could imagine (I can not to this trick) that with shorter cranks it will be even more difficult because you stand even more far away from the peg. But in the end you might get used to it and of course they are lighter...Maybe a view on the scene helps. Look at the pros. I hardly see any rider with cranks below 160 mm (at least what I can see by eye). I would say some years ago people were experimenting with it and then 160 mm or 165 mm became a standard more or less. You can not go so wrong with these sizes.

Online aliasdck

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Re: Crank arm length
« Reply #5 on: November 26, 2019, 07:35:42 PM »
Thank you Daddycool, I think you're correct on all points. I don't see any reason to go with a shorter length than I'm already to used to, so I will be sticking with 160mm.