It was pretty heavily rumored for a few months, and now officially, SRAM announces what everyone already knew: Fat bike cranks are coming. First let’s get you caught up with what exactly will be available, then we’ll end with some of our thoughts on the subject….
SRAM Tech document that surfaced last year
The crank sets are being made by SRAM in double ring versions only. 10 speed, 36T and 22T equipped doubles that are said to eliminate “most tire to chain rub found on fat bikes“. We take this to mean that perhaps the spider has been positioned in a bit more of an outboard manner to not only get the better chain clearance, but to give better chain line with both rings. We suspect the chain clearance bonus was secondary. 😉 SRAM also claims lighter weight “than most current fat bike crank offerings“, which considering the current offerings, is not saying much. Still, fat bike aficionados should be pleased with the promise of more, quality selections for fat bike use.
The X-9 level offering.
The X-5 level offering
SRAM lists the X-9 fat bike crank at MSRP $314.00USD and the X-5 at $169.00 USD. There was no word on when the cranks might be available to the aftermarket. However; we do not believe that SRAM is simply being altruistic and giving the fat bike fans a better quality aftermarket choice here. No…..we’re thinking this points to something else.
Typically SRAM, (or any of the larger component makers), doesn’t tool up and produce products for the aftermarket only. Yes- we are thinking some company, or group of companies, is going to introduce fat bikes in their line up for 2014. While it is true that Salsa Cycles or Surly Bikes will likely make use of these components and will account for some of the production, we do not feel they are the only ones behind this. All we can say now for sure is that we’ve heard rumors, and well…….time will tell if we are right, or if we are wrong.
At any rate, this development gives the fat bike a stamp of acknowledgement, (at least), by the industry, and signals that we are likely to see more fat bike developments coming in the near future.
NOTE: This report was put together with information and images provided by SRAM. We thank SRAM for sharing with us and the readers of TNI.
Wouldn’t Surly/Salsa/QBP just make their own cranks for fat bikes if their was an inhouse need? With a Q factor of almost 190, can we take 150 as normal, then take 1/2 of the difference(20), and say that this is the amount that the fat cranks are sifted to the right?
I hope you understood what I was trying to say…
this is the smallest q factor fat crank ever! Switching from a stock mukluk from 2012 with truvative to this is 26mm
@yogi: Surly has a couple different “fat bike” cranks already, but they are heavier than the X-9, and dare I say- not as good looking.
Salsa does not have a house branded crank, and i do not foresee that ever happening now.
so the SRAM X9 is more expensive than the e*thirteen XCX, is heavier, and has the same chainline offset. 66mm
meanwhile, the Surly MWOD has a chainline of 82mm
and the e*thirteen TRS that is currently exclusive to Salsa, has 73mm.
(to round it out, Race Face has 67.5)
To clear a 4.7″/4.8″ tyre, on an 80mm plus rim, with a dual chainring setup, you’ll be wanting at least 73mm.
So the SRAM offerings, while nice, won’t work with the latest really fat tyres.
and the weight is……………….?
I have a sweet idea for a fatbike crank. You shape the chainline like a MWOD but then you keep the crankarm straight and closer to the chainstay. Finally make a small cutaway on the inside edge near the pedal spindles (similar but bigger than this tech drawing is showing).
It looks like they could have mounted the big ring on the outboard side (who needs bashrings anyway). I wonder how much extra clearance that would give.
So are the rumors that some of the big guys are going to be doing Fat bikes?
I guess we will be seeing a S works fat or Blur fat by next winter.
Technically not a ton of fancy tooling is needed to adapt current designs to fat bikes….just lengthening the spindle.
That said, I do enjoy the prospect of the big boys getting into fat bikes. Know for a fact TREK and Specialized are testing designs out. Sure many of the mid-size companies are considering as well (Raleigh is one who I suspect will in 2014).
@All: Concerning chain line- This is what I learned from @ Frostbike. SRAM were not willing to sacrifice what they term as “A” shifting precision for a fat bike drive train. In their view, moving the spider outwards in an effort to clear the biggest tire/rim combinations was not going to work without compromising that “A” level shifting precision. Also- they feel that the market is centering on 80-ish mm wide rims and 3.8″ to 4″ tires, with the 4.8″tire/100mm rim combination being less likely to be the bigger share of the market. Furthermore; SRAM feels the 4.8″ tires on 100mm rims really requires a 190mm hub and wider BB to make the shifting work the way they would want it to be. Obviously those dimensions are still being developed and may not take hold of the larger share of the fat bike market.