Actual difference in stiffness between Next SL and XT.

I'm a sucker for carbon cranks.  Broke two set's of E*13's DH cranks within a few months of each other.  Had two sets of SRAM's DH cranks.. had one for a full year, got a second set because I was a bit worried about longevity and then proceeded to break the second one on my third lap on an innocent pedal hit on Angry Pirate.

As for this year.. did a full 130ish day season in the bike park on SixC cranks.. good job RaceFace (except your bearings.. they're crap).

So far so good for me on my SixC and Next R cranks although I don’t ride nearly as much as some people here. 

I AM lusting after the eeWings cranks though!

Every time I look at the gouges and chips in my XT cranks  

I wonder how carbon would have fared in the same place?

But the main reason I am on Shimano right now is because you can install & remove the cranks with regular Allen keys, with no need to torque the crap out of a crank bolt. Seems to be changing with the new XTR though...😢

I'm a 220lb+ rider. Broken lots of things; frames, forks, cranks etc. I think the bigger you are, durability counts for a lot more than does "stiffness." Performance counts for something naturally, but if it fails after a season or two, is it really a better performing product? I haven't put carbon cranks on my bike in years and I never feel bad about slamming my turbines into anything. I don't even have crank boots, why would I cover those rad gouges? 

My favourite part of my turbines is the cinch chairing that never seems to bend despite being slammed into it's fair share of logs. I always hated bending the spider on my old cranks - shittiest design ever. Making the weakest part of a crank stronger and replaceable is genius!

Posted by: bogey

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I AM lusting after the eeWings cranks though!

Indeed. I just want to lick them.

I'm 200lbs ready to ride and I have only noticed stiffness issues with some carbon wheels and some 35mm carbon bars. Both of which can degrade the ride quality by transmitting more vibration than less stiff alternatives. As far as cranks go I have over 5yrs on Next SLs with no issues and just got a set of Next R's at the start of this summer. The cranks and RF's BBs have worked well for me both threaded and PF varieties. 

I just got a Boost bike and can't tell any difference from my 100/142 bikes that I can trace back to the wider hubs.

I'm shopping for a hardtail at the moment and I am doing my best to find one with a pleasant amount of flex for my weight/power and avoid an overly stiff frame.

The MTB industries constant marketing spew about more and more and more stiffness is stupid. You don't want the stiffest bike possible. You want the various components of your bike to be appropriately stiff for your needs. That gets too complicated to discuss in an advertisement sound bite so we are left with "MOAR STIFFERER THAN EVER!" ;)