I recently picked up a 170mm SRAM X5 fat-bike crankset for the Schlick 29-Plus prototype I built up and initial impressions are, well, impressive!
Weighing in at a real world 959 grams, the black, X5 fat-bike cranks have a 100mm wide spindle and dedicated 36/22 SRAM 2X10 chainrings. For those with longer legs than mine there is also a 175mm version available. Either way, expect an MSRP of $169.00.
Installation was easy in the 100mm faced and reamed shell of the Schlick. The GXP BB has a sleeve over the spindle inside the bottom bracket and a removable seal on the left side while the right side uses a plastic hat sleeve on the outboard bearings. Using the correct shell spacers, 2 x 2.5 in the case of a 100mm BB, and snugging up the left crank arm bolt where all that was necessary to complete the install and the cranks were smooth turning with no side play. I wish all crank installs went so easily!
On the initial rides the crank basically disappears. It just does its job, seems stiff enough for me and the SRAM chainrings work well with the SRAM X9 front derailleur I have it paired with.
The X9 fat-bike crank also recently became available so look for a report on that as soon as we get in a build that uses one! The main difference from what I can see is that the X9 is lighter and stiffer due to a hollow forged crank arm. It is also nearly twice as expensive!
I bought this crank with my own money and the opinions are mine. No undue influence came from the manufacturer.