The Truvativ X0 Silver BB30 2.2 10-Speed Crankset is modern in every way with carbon fiber arms and a dedicated dual chainring configuration, but its polished aluminum spider and big ring cutouts give it some old school bling. This BB30 version has a narrower spindle than the GXP version, offering more heel and ankle clearance. This is a big deal if you're a toe-out pedaler. With BB30 cranks, you can say goodbye to the incessant grinding between your muddy shoes and the crankarms.
This X0 Silver GXP 2.2 Crankset uses carbon fiber like the top shelf XX crank, but there are a few differences. Unlike the XX crank, there's no alloy spine connecting the threaded pedal insert and the crank/spindle connection. SRAM engineers figured out a way to eliminate it, instead using a stiff structural foam core inside the composite skin. Don't think for a second that it's weaker; part of SRAM's goal for XO was to make it burly enough to handle the rigors of all-mountain riding.
Another difference is that this XO crankset uses an aluminum spider where the XX spider is an integral part of the carbon crankarm assembly. While it's a few grams heavier, the XO system allows you to remove the spider if you want to change from two to three rings or vice ...BB30 and dual chainrings with modern technology and old school bling... versa. As is, this 2x10 setup has a bolt circle diameter of 80/120mm. Of course, it's an exclusive measurement, but for the chainring tooth combinations SRAM wanted to offer, it optimizes the stiffness of the rings. And stiffer chainrings mean quicker, more precise shifts.
Not only did they design their own optimized bolt circle diameters, but they re-engineered the shift ramps, pins, and cut outs on the outer chainring. On most chainrings these days, there are two sets of ramps and two drop points where the chain can get lifted or dropped quickly and under pressure. This means that twice each pedal revolution you'll hit these spots, so the shifting can be iffy if you shift at any other time. You've probably experienced this with the pause and clunk and sometimes smooth movement on other crank systems. SRAM's X0 outer ring allows perfect shifts just about all the way around the crank. They call this X-Glide. Another improvement stems from having only two rings. From the small ring, the chain can only go up, from the big ring, only down. With this in mind, each ring can be shaped specifically for its more focused purpose.
The Truvativ X0 Silver BB30 2.2 10-Speed Crankset has Clear Coated Carbon fiber arms with a polished and clear anodized 7075 T-6 aluminum spider. The chainrings are made from the same 7075 alloy and have polished accents. It's available with either 170 or 175mm crankarms and comes in two chainring options -- 26/39 or 28/42. It requires a BB30 bottom bracket (not included) and will only fit in frames that are built for BB30 or PressFit 30 standard bottom brackets.