2x11 configuration Reduced weight Carbon-reinforced titanium alloy chainrings Computer-optimized shift paths DOUBLING DOWN ON THE TECH. Shimano has come around to understand the benefits of a single-ring drivetrain system, and so it offers a single-ring crankset option with its new XTR M9000 groupset. But that didn't detract any of the focus from making the Shimano XTR FC-9000 2x Race Crankset the best race-ready double-ring crank it's ever made. The new XTR M9000 crank arms do not deviate enormously from Shimano's consistently-proven formula of hollow-armed alloy arms with proprietary spider and ring technology, and we are grateful for this, although there are notable enhancements. The adaptation of an 11-speed platform allowed engineers to hit the reset button on a few areas. Of note is the fact that the left-side crank arm is now hollow-bonded, a manufacturing process that saves weight over previous production methods without giving up strength. The right arm likewise boasts reduced weight while also playing host to a new four-bolt spider that is compatible with all double or single chainring configurations that Shimano now makes for the new 9000-series cranks. Those chainrings received enormous amounts of attention in the redesign, too. Like the crank arms, the rings are also hollow to save weight, but their rigidity has only increased over the last-generation XTR rings, thanks in part to revolutionary carbon-reinforced titanium-alloy construction. Shift paths are computer-optimized for smooth and virtually instant shifting. The teeth are also titanium, and the outer ring's teeth are even hollowed out to shave as many grams as possible.
