When it comes to making your bike sing, you'll need to compose just the perfect chorus, and with Campagnolo's new Chorus 12 Rear Derailleur it stretches beyond previous years, and into the realm of twelve-speed drivetrains that stay cool and composed up intensely punchy climbs, and let you hit serious high-notes when you soar down canyon descents. Like previous Chorus derailleurs, this one receives heaps of trickle-down technology from its Record and Super Record brethren, but makes some concessions -- specifically, in the weight department. As it skips some of the more exotic materials in its construction, it scales in at 4 and 39-grams heavier than its siblings, respectively, which does hold some water in comparison, though as far as function goes, the Chorus utilizes the same internals and updated 12-speed compatibility, but with a price tag that's much more palatable to those of us who are self-sponsored. Campy didn't just create the new Record and Super Record group to add in an extra cog, although we do appreciate the wider range that it affords without having massive jumps between the sprockets, it took the opportunity to redesign the group entirely and build the best mechanical group it knew how to make. As such, it features 3D Embrace technology which places the 12-tooth pulley wheel closer to the bottom of the cog, increasing the chain engagement and management over rough roads and more precise and faster shifts. The derailleur's cage has also been engineered so one cage length works with all three Chorus 12-speed cassettes offerings (11-29t, 11-32t, and 11 - 34t). Its technopolymer upper body shaves grams without sacrificing strength while the parallelogram maintains the same polymer, and front plate opts for aluminum to keep cost pocket-friendly. Carbon fiber elements on the lower body add a sleek aesthetic to keep with the looks we expect from Campagnolo. Campy's Ultra-Shift geometry reduces friction for smooth shifts across the cluster all while ...