Buying a new chain set? Does it matter how long crank arms are.? Some scientific folk have formulas ....
Theories vary - I've tried everything from 120mm to 185mm.
175mm is common on an mtb. if you are short then shorter may feel better. if your bike has a low bb then shorter may feel better
I have always had 175mm on mtb's. However reading various threads on the matter I would go to 170mm if I could get it at a much better price.
It seems many folk don't notice much difference at that kind of change and it can help with clearance. However I have yet to try a different length!
Shorter cranks can feel nicer if you like to spin, but I find it hard to tell the difference on an MTB.
I'm 5'10 with 32" inside leg, 175mm or 170mm are both fine for me.
If your knees are particularly knackered then shorter cranks put them through a smaller ROM which can stave off anterior knee pain.
I've just swapped from 175 to 170 on all my bikes. My knees feel much hapier now.
170mm but would love 165mm but Sram don't make them.
Ok sounds like 170mm it is....
A good friend of ours recently went to 165. Only ones she could find were xt.
[i]Ok sounds like 170mm it is.... [/i]
Eh, what makes you say that? It depends on how long your (inside) legs are.
I went shorter on recent XT bargain from Merlin. Cant tell the difference
I like 180s, cos i'm a lanky git. Feels more comfortable.
Having said that, I have 175s on the AM bike and it's not the end of the world.
If I put my hands in my pockets I can jangle my balls.
I think my arms are just long enough thanks.
I like 180s, cos i'm a lanky git. Feels more comfortable.
^this
I replaced the 175 cranks on my old Stumpjumper FSR with 170 cranks. Only got them because they were cheaper than the 175.
But, they don't feel any different when riding and the problem of pedal strikes all but went away.
In a reverse twist, I went for 175 cranks on my road bike, instead of the 170 it came fitted with. Again - they were cheap, so I figured it'd be OK.
I now get toe overlap with the front wheel, that I didn't get before. Probably should have stuck with 170 cranks, but didn't even consider this would be an issue.....
I'm lankier than most and have 180's on my FS, 175 on everything else.
Can't say i've ever noticed a difference between them.
That new bike company in the US (36ers for 6'6"+) uses 220mm cranks....
