# Crankarm Length For A Tall & Heavy Rider



## nbritton (Jul 26, 2016)

It's time for a new crankset, but I'm not sure if I should keep the stock 175mm crankarm length or go to 180mm. I'm looking at ether a Shimano FC-M670 (SLX) or FC-M780 (XT).

About me:

Height: 6' 3"
Inseam: 34"
Weight: 290 Lbs.
Bike: 2013 Trek Rumblefish Elite 29er


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## DABIGSEAT (Apr 29, 2012)

I would keep the same length, iim 6'6 and use 175mm with min pedals strikes

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## jeffj (Jan 13, 2004)

Be careful if considering shorter cranks to avoid pedal strikes, as some manufacturers use the same length crankarm with the pedal hole merely drilled in a different position.


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## watts888 (Oct 2, 2012)

6'5" with 175 cranks. I wouldn't want anything longer. If it's for road or gravel use, maybe something longer. For trail use, 175mm


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## NYrr496 (Sep 10, 2008)

I'm 6'5" and I have 180mm cranks on two bikes. Everything else has 175. I like the long cranks. I truly believe if I strike anything, I'd do it with 175mm cranks also. 

I haven't had a strike in a really long time.


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## TooTallUK (Jul 5, 2005)

Around here you're not that tall and not that heavy!

try them. Some like them (I do), some don't.


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## Nubster (May 15, 2009)

Yeah...6'3" really isn't _that_ tall. I'm 6'2" and don't consider myself tall at all. As far as crank length...175 is perfectly fine. I don't think you'd need to consider longer unless you were quite a bit taller. At 6'2" I was actually throwing around the idea of going shorter to 172.5 but after some research...I decided to stay with 175. Some pros on the road are going shorter so there might be a little something to it...but any tiny benefit you'd get would be something you would have to be a top level pro to realize. And top level I am not. And I really don't think that on a mountain bike...2.5mm shorter, if the crank is actually even any shorter...is going to do much or anything to help prevent strikes.


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## MichaelInOr (Aug 16, 2016)

I am 6'3" 34" inseam 230lbs. I rode my 2009 Turner Sultan with 180mm cranks back to back with several different bikes from LBS's with 175mm cranks. I love my 180mm cranks and 175mm feel too short for me. Obviously I bought the Sultan with 180mm cranks.



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## Tjaard (Aug 17, 2007)

Theoretically a longer crank might fit your leg length better. But, pedal strikes will slow you down more than a slightly short crank.
I would say, if the bottom bracket is pretty high and your trails smooth, sure, go with the 180s. If it's a low bike or your trails are rocky or rooty, stick to the 174s. Is there a price difference?
I am 6'5", 37" inseam, and switched to 170s on my current bike to prevent pedal strikes. I notice no difference to the stock 175s. I did ride 180s several years ago, again could not feel a huge difference.


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## schnee (Oct 15, 2005)

There's a bunch of research out there, and it points to there being little practical difference in an extremely wide range of crank lengths. In fact, there could be a slight benefit to using *shorter* cranks.

Crank Length ? Does Size Really Matter? - PezCycling News
The Benefits of Reducing Your Crank Length | TrainingPeaks

I'd stay with 175 or shorter due to bottom brackets assuming they have to handle that length on production bikes, and lower bottom brackets in general due to the current 'long low slack' trend.

Additionally, I'm your size, I tried a bike with 185mm cranks (a custom hard tail) and it felt really weird and fun, but didn't make much of a difference in my overall performance.

HTH.


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## Gigantic (Aug 31, 2012)

I'm 6'8" and 265#s, I use 175mm cranks on my mountain bikes because they're readily available and because my local trails are rocky, root and log infested; longer cranks would increase the incidences of pedal strikes. YMMV


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## phoeve (Mar 10, 2008)

I'm am 6'8" and ride 200mm cranks. Go at least 180mm !


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## lowestbarone (Nov 10, 2011)

You're unlikely to notice the 5mm difference TBH. Get 180 if you can but don't go out of your way/budget to get some.


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