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[Closed] 175 v 170mm crank arms. Will I notice the difference?

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Obviously one set is going to be 5mm shorter than the other but will I notice?

Pros/Cons??

Currently got 175 and some 170 have come up at the right price?

Thanks


 
Posted : 12/08/2014 8:43 pm
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I noticed when I went from 175 to 170 but I did it because of knee trouble.


 
Posted : 12/08/2014 8:45 pm
 gee
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I swapped to 170s a few years ago as I thought it would help my knees and ground clearance, Turned out that both problems went away and I'm now back on 175s as I can definitely feel the greater leverage.


 
Posted : 12/08/2014 8:46 pm
 DezB
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Clearance is about the only pro. Some people notice, some don't....


 
Posted : 12/08/2014 8:46 pm
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Leverage? Wouldn't have thought 5mm would make a difference you'd notice.


 
Posted : 12/08/2014 8:49 pm
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Yes.

I'm a shortarse with old knees.
They really appreciate the difference.


 
Posted : 12/08/2014 8:50 pm
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I switched to 170 from 175 to try and rectify a knee issue and it made a huge difference. I can now ride more than 20k again!

It's not the cranks that fixed it its just not aggravating the issue as badly (I should fix the root issue really), but for me it's a winner. IF you have no issues with 175 I don't see why you'd bother though?


 
Posted : 12/08/2014 8:52 pm
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I smashed 3 pedals in 2 months after changing to 175mm crank arms.

CHanged back to 170mm now and not broken one since, make of that what you will ๐Ÿ˜€


 
Posted : 12/08/2014 8:53 pm
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Well that 'right price' was just that until the last 60 seconds, then they doubled in price. Dam those EBay snipers

Thanks for the replies though


 
Posted : 12/08/2014 9:01 pm
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Actually noticed more on my road bike and my fatty than on a mtb. Yeah, you get more leverage (fractionally) on 175, and you get less pedal strikes on 170, but the kicker is what its like for your knees. I thought I was fine in 175, tried some 170's and have never looked back, they're way better for me. Obviously on an mtb, changing height and stance more, that's somewhat of a moot out for some people.

If you can get em for a price where you won't lose much/anything flogging them on if you don't like it then it's worth an experiment. You could love them, hate them or not notice any difference


 
Posted : 12/08/2014 9:05 pm
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Clearance was my issue....so I went 170..........but it does seem to suit my dodgy knees....so I have 170 on three bikers now.....and I don't notice any leverage issues


 
Posted : 12/08/2014 9:23 pm
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I was looking at 2x10 XT cranks yesterday and noticed that the 165mm length version as a max outer ring of 38T whereas the 170mm and up have a 40T option. I guess Shimano are factoring in some loss of leverage?


 
Posted : 12/08/2014 9:27 pm
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Going from 175 to 170...

Drop the saddle 5mm to be right at the bottom of the stroke and then its 10mm higher at the top, worse on 180mm cranks, i think thats where the knee problems come from, the top of the crank stroke.

as for leverage, as Sheldon says, any advantages are negated by choosing a different gear.


 
Posted : 12/08/2014 9:33 pm
 DezB
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[i]as for leverage, as Sheldon says, any advantages are negated by choosing a different gear.[/i]

What if you're in top gear?


 
Posted : 12/08/2014 9:35 pm
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170 cranks on summer road bike
175 cranks on TT bike
175 cranks on winter road bike
175 cranks on CX bike
175 cranks on singlespeed MTB

The 170s feel like I've got less leverage, that 5mm is noticeable on certain bits where I feel like I should be able to push more but can't.


 
Posted : 12/08/2014 9:36 pm
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in short: yes, no, maybe.

I have 175s on my mtbs - once tried 170s and they were way too short.

i have 175, 172.5 and 170 on road bike and can't tell the difference!?


 
Posted : 12/08/2014 9:42 pm
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Obviously one set is going to be 5mm shorter than the other but will I notice?

cranks will be the same length, the hole for the pedal spindle is 5mm further away from the end though


 
Posted : 12/08/2014 9:45 pm
 br
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Depends on how long your legs are, I think?


 
Posted : 12/08/2014 9:45 pm
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Always been 170 or though on occasions 165. MTB though is 175 coz that's default. Got those on the roughstuff bike but will go back to 170s.Some how feels nicer and as my natural tendency is to pedal a bit slow shorter cranks make twiddling easier.
I wonder what my 165's will feel like?


 
Posted : 12/08/2014 9:46 pm
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I've used various lengths of crank and couldn't tell the difference at all. Basically, everyone is unique and special: some people are highly sensitive to crank length, and some people aren't pathetic princesses. ๐Ÿ˜‰


 
Posted : 12/08/2014 9:48 pm
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I've used 165, 170, 172.5, 175 and 180 between road & mtbs - not felt a difference in the pedaling with any of them but then I'm not one for spending hours in the saddle so others (like gee, say) may spot it far easier


 
Posted : 12/08/2014 10:56 pm