Crank Length?

I have to dig this up again. how big is the difference really between a 165 and 170mm crank?

5mm?

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Pedal strike fear, a very real condition.

I'm 5 11" with a 34" inseam. Use bike only on street with some hills not very steep. I ride 170s geared. Online calculators give 170-172.5mm. What length do you suggest for 48x17? Should I go for 165 or 167.5?

^ according to my personal experiences crank length should be based upon bottom bracket height/pedal to ground clearances...

if you prefer to spin at high cadences than 165's will be the bet
... but if grinding larger gears at lower rpm is more your thing than longer arms will give you more leverage resulting in higher torque

I ride 165mm on track frame with lower GI than 170mm mtb/fixed conversion and enjoy both for their intended purpose

Hope this helps

^ Wow... Actually speechless!

Just get 170s.

Apparently it makes no difference when the lengthened stroke has been taken in to account by the fit.

Buy the cheapest one, or the shortest for tarck en street

Providing its not a road Conversion with a low BB 170mm would be fine.

But if youre 170mm based on leg length. I Guess 165 - 175 is going to feel absolutely fine.

Im 169cm (no shoes) in height

Currently ride 172.5mm cranks
Thinking of changing to 170mm

Whats the current thoughts on cranks to height ratios?

Impossible to tell on height alone, but I'm 173cm and ride 170mm.

Was looking into this as I have a fair bit of toeverlap on my new build (frame has a steep head tube for short trail, rando-style, plus mudguards) and I seem to dimly remember that I decided to go for 170mm cranks (and promptly forgot, fitting 175s instead). I thought that fitting shorter cranks would be weird for a taller rider (180-something)but as I was reading up on it the latest consensus seems to be that there's virtually no difference in terms of biomechanical suitability, but rather the only measurable difference was that when using shorter cranks, O2 uptake was lower because the rider is effectively pedalling a slightly shorter distance overall (which I guess would add up over longer rides). It seems weird but made some kind of sense when broken down like that, and begs the question of why significantly shorter cranks aren't produced to accommodate shorter riders? And does it make sense for me to drop my crank length t0 170 or even 165, whatever it takes to get my toeverlap under control?

Hope make 155mm cranks, but claim it's to do with pelvic twisting and stability (or something, I stopped reading) but aimed more at MTBers.
Anecdotally, I'm 188cm and got bikes with cranks varying from 167.5 up to 175mm and I cannot tell any difference swapping between them.

https://bikepacking.com/gear/crank-length-test/

Make of that what you will.

Good to know!

That's a really interesting article - broadly confirms what other tests seem to indicate but it's good to see just how short people can go and still not see much major difference.

I’ve just gone down to 160mm (im 179 tall) and power definitely hasn’t gone down (I do a specific workout once a week so can see). It’s maybe gone up, but hard to confirm that’s the cranks.

I wouldn’t know that I was riding different lengths, but I went for a bike fit and when we changed the length whilst I was on the bike I noticed it when tucked. The guy didn’t tell me what length we were at until afterwards.

I’m 182cm and have cranks 165mm to 175mm on different bikes.

I normally don’t consider myself a very refined or sensitive cyclist so don’t notice small changes in things but crank length is one area where I do feel I can sometimes tell the difference.

I only ride singlespeed and fixed bikes and I prefer a lower gear/higher cadence and I feel like the 175s are mostly too long for me, I don’t like spinning such big circles.

The only bike I have them on at the moment had a hub gear but I broke that last week and have singlespeeded it, haven’t done much riding on it to see how I get on with it.

I had been running 175s on my mtb (thinking greater leverage would be better on technical climbs) but my most recent bike has a low bb so I dropped to 170 and haven’t noticed any negative effects, I’d like to go to 165 but with 165 mtb cranks being less common they’re more expensive so haven’t done it yet.