170mm cranks for 5ft 10.5inch rider?

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pdlpsher1
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by pdlpsher1

Funny thing is, I won't notice a 2.5mm change in saddle height but I do notice a 2.5mm change in crank length. I think this is because a 2.5mm change is really a 5.0mm change since the crank rotates around the axle. The crank is longer at both the 12 o'clock and 6 o'clock positions.

Go for the 170mm. You will like it.

by Weenie


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Allen254
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by Allen254

Shrike wrote:Also have a 31inch inseam. Industry standard seems to be 172.5mm, but would like to try 170mm.

http://bikedynamics.co.uk/FitGuidecranks.htm

Seems most recommendations are a bit shorter than industry standard.

Also apologies for question spam recently :P

any rider of any height can rider which ever crank length but you will have to adjust saddle height.

DaReef
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by DaReef

I'm 5'11.5" and use 170mm.

Racingevo
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by Racingevo

I have the same inseam and I use 170 when I upgraded my crank to Ultegra 6800. I definitely did notice a difference for the better. My cadence increased slightly but it's hard to empirically prove that. I can climb out of the saddle a lot longer with the shorter cranks and if I were to do it again I'd go for 165mm but I'm stuck for the time being since I got a stages crank arm power meter.

Bridgeman
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by Bridgeman

I need more money.

mattr
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by mattr

stormur wrote:Is thickness of all road shoes equal ? Or can vary even 3-4mm ? insole thickness ? Sock ? Pedal stack ?
none of which make the slightest difference to the circle to which your foot has to pass through. Crank length does.
Allen254 wrote:any rider of any height can rider which ever crank length but you will have to adjust saddle height.
they'll also need to have their knees operated on eventually.

RussellS
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by RussellS

I am 5'11" tall. I use 175 cranks on my seven geared road bikes. 172.5 and 170 on my two single speed bikes. Mainly because those are the cranks I had in the spare parts box when I built the single speeds. Never notice any difference when riding geared and single speed bikes on back to back days. I can spin 90 rpm comfortably all day long on any crank length.

racingcondor
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by racingcondor

I'm 5'11" (33 inseam and UK size 12 feet!) and moved to 170 cranks after riding 165's on track.

I can feel the difference but I doubt that there is a measurable performance difference. I'd imagine the only difference in reality is the reduced likelihood of pedal strike when riding through a tight corner.

RedCoke
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by RedCoke

I think inseam is more impoart factor than height only.
inseam(mm) x 0.216?

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Mr.Gib
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by Mr.Gib

RedCoke wrote:I think inseam is more impoart factor than height only.
inseam(mm) x 0.216?


That number doesn't seem correct. A factor of 0.216 would have me on a 190 mm crank. I am 6 feet (183 cm) with average proportions. I am happy with anything up to 175 mm. I prefer 170 mm due to past knee injuries, and spinal injuries.
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tinozee
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by tinozee

Checkout slowtwitch forum for more comprehensive discussion on this. Short crank arm is fine. Watch out for nutty ideas like Lennard Zinn's long cranks.

joeyb1000
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by joeyb1000

LloydP wrote:I'm very close to your proportions and use 170mm cranks. It works fine for me. Try it and see!


same here.

Allen254
Posts: 144
Joined: Sun Feb 07, 2016 3:05 am

by Allen254

mattr wrote:
stormur wrote:Is thickness of all road shoes equal ? Or can vary even 3-4mm ? insole thickness ? Sock ? Pedal stack ?
none of which make the slightest difference to the circle to which your foot has to pass through. Crank length does.
Allen254 wrote:any rider of any height can rider which ever crank length but you will have to adjust saddle height.
they'll also need to have their knees operated on eventually.


:roll:

RedCoke
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Joined: Fri Oct 28, 2016 8:54 am

by RedCoke

Mr.Gib wrote:
RedCoke wrote:I think inseam is more impoart factor than height only.
inseam(mm) x 0.216?


That number doesn't seem correct. A factor of 0.216 would have me on a 190 mm crank. I am 6 feet (183 cm) with average proportions. I am happy with anything up to 175 mm. I prefer 170 mm due to past knee injuries, and spinal injuries.


It is "inseam(mm)" not height. Please check this.
http://www.stevehoggbikefitting.com/bik ... which-one/

by Weenie


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RedCoke
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by RedCoke

Also, this site would be helpful.
http://www.peterwhitecycles.com/

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