Are there any 'real world' advantages to be had by increasing or reducing crank arm length.
Rode my Wife’s Small Stumpjumper Carbon HT and it really did seem fast, easy to get up to speed and generally very racy, more so than my Med Scott.
A pal who is a Specialized dealer said it has 170mm Cranks.
Could that be the reason?
Very interested in this one as I came on to post exactly the same thing. Building a bike for my son and was going to give him my old XT cranks with 175mm crank arms but as ghe is only about 5ft 3" thought that perhaps 165mm or 170mm might be better.
I you put 95% of riders on a bike with 175mm cranks and then put them on the same bike with 170mm they wouldn't know the difference.
Its like a 3% difference in crank length!
EDIT Very short or very tall rider being the other 5%!
daveb.
You got me thinking, just took a look at the cranks and they are infact 165mm. So a full 10mm shorter than Im used to.
It really does seem to make a difference.
On the other hand I could have been just having a good day.
Rode my Wife’s Small Stumpjumper Carbon HT and it really did seem fast, easy to get up to speed and generally very racy, more so than my Med Scott.
A pal who is a Specialized dealer said it has 170mm Cranks.
This is more likely due to just being a different bike.
yeah, it's more to do with your wife's bike being smaller and lighter
JoB.
Could be down to the size, my bike is actually considerably lighter though.
Might try the Crankset on my bike.
Just to see.
Interesting though.
It's nicer and more efficient to have shorter cranks with higher cadences, so you will usually have longer cranks on road bikes then mountain bikes. Longer cranks give more leverage, so you can get more power down, but only makes a slight difference I think.
you will usually have longer cranks on road bikes then mountain bikes
I thought it was the other way round?
I've got 170mm cranks on my HT and 175mm cranks on my FS, the HT seems a bit spinnier if that makes sense
I thought it was the other way round?
+1
I think he did too. typo?
Also:
Longer cranks give more leverage, so you can get more power down
No. Longer cranks let you get more TORQUE down, but being longer, spin slower, so less power.
So longer cranks are more suitable for mtb, where slow-speed high torque technical climbs are common.
I think he did too. typo?
Yeah, meant to write "shorter cranks on road bikes", oops.
No. Longer cranks let you get more TORQUE down, but being longer, spin slower, so less power.
Ugh, I'm tired, leave me alone 🙂
Do low speed, high cadence climbs look less ridiculous if you feet are moving in smaller circles?
It's pretty much a moot point though not many cheap 165 mm or shorter MTB cranks out there (been looking for my GF's bike)
i have 170 on all bikes because it ended my knee problems thats the only reason.
I have no idea how long the crank arms are on my 5 bikes.
I'm 5'6"
Got 175, 170, 165 (and 153 on my commuter/child seat bike).
165 easily feels best - got that 'always in the right rev range' feeling. Yeah, Problem is finding a set that is not ££££££.
175 feels terrible - huge empty stroke feeling.
I'm oblivious to it, I've got (I think) 2 sets of 170s and 2 sets of 175s, but can't remember which ones are on what.