glore2002

Hello!
Since there are many and different opinions about cranks length, I feel a bit confused and in order to clarify this subject (at least for myself :-) I would really appreciate your help.

My height is: 1.80 meters or 5.905512 Feet or 5' 10.87".

I want to change my crankset for a Shimano Alivio one. Available sizes are 170mm or 175mm. Which one should I get? Which one would you recommend me to get?

Thanks in advance,
glore2002.-

tellyho

I'd go for the 175s. Make sure your bottom bracket will be the right size for your new crank.

womble

175. A length of 170 is pretty short.

DMF 

170 isn't that short. And 170s give better ground clearance.

You could go either way. On an MTB I'd lean toward 170.

55-11

is a 172.5 vailable like in road???

Neccros

175mm no 172.5 isnt common in a mountain crank... 170 or 175 is most common

55-11

look at that...even I can learn something new when I'm not trying to be a know-it-all

FlatFender

Im a bit bigger than you, and I honestly cannont tell a difference between 170 and 175. So, I run 170 on all my bikes.

well biked

170mm was the "standard" for a very long time. Mountain bikes came along, suddenly 175's were common, the selling point being "more leverage." I've used both extensively, I'm 5'9," honestly I don't notice the difference. When I bought Nashbar touring cranks for my tourer/commuter a couple of years ago, I saw that they were available in 170, 172.5, and 175. I said what the hell, I'll go with the 172.5's-........FWIW, if you were to buy a new mountain bike, and found one that fits you at your height, there's about a 99+% chance it would be factory equipped with 175mm cranks-

glore2002

Thanks for your help. So, as a conclusion, it is almost the same choosing a 170 or a 175 mm crank. So, I wont feel much difference between those two lengths.

Thanks again for your help.
glore2002.-

z415

You will feel difference if you are riding on pavement - when commuting I feel that the 175 gives me distinctly more leverage and consistency when spinning. That being said, I regret having 175 on my mtb because I smash into everything; any "advantage" the longer arms give seems useless unless where you ride is straight and flat.

Sometimes I do feel that the longer arms give me leverage on really hard climbs, but I only feel that when spinning really slow and riding a hard gear which I don't recommend you do because I've heard it is hard on the knees.