Inside Greg Herbold's lair, our XX1 loaner bike gets assembled by SRAM's Chris Hilton and Andy Benz. One look at a bike with the XX1 drivetrain and every front derailleur and chain guide-equipped bike looks cluttered and antiquated. Note the initials on the seatstays— H-Ball's personal bike. Note to self, rubber side down. Another note to self, those are some pretty narrow tires on for Moab, we're going to get schooled.
If you are lucky enough to be an XX drivetrain owner, you already know how good the cassette is. The same zero flex, machined steel masterpiece is used in the XX1 group. However, the XX1 cassette has 11 cogs ranging from 10 to 42 teeth. This spread is sufficient for most riders to tackle nearly any terrain with just one ring up front.
The XX1 ‘Straight-P’ rear derailleur is a clever twist on most rear derailleurs on the market today. We use twist because the parallelogram has been rotated sothe movement is horizontal, hence the 'Straight-P' name. Having a horizontal parallelogram keeps the derailleur from bouncing over bumps. This design, coupled with SRAM's Type 2 derailleur clutch, eliminates the need for a chain guide.
While the cassette is impressive and the rear derailleur is innovative, the real game-changer is the chainring. The ring is 'timed' with even numbered teeth that alternate between thick and thin to match the wider and narrower inner profiles of the chain. What does this mean? It means your chain will simply not come off. We know what you're thinking—ride hard and that chain is flying off. We didn't believe it ourselves until we rode it.
After two days of hundred-degree riding, which included the majority of the Whole Enchilada (we'll call it four-fifths of the Enchilada), we came away from Moab with two profound truths. 1) Moab is some seriously hard riding. 2) We love this drivetrain, and will be purchasing it for our personal bikes. If the chain didn't come off in Moab, it won't come off anywhere.
One closing consideration. XX1 will be offered with a trigger or grip shifter. We preferred the trigger, as it has a slightly more refined feel. The grip shifter allows for very fast shifts, but shifting too fast across the whole cassette will result in less than optimal performance. This is not possible with the trigger, due to the solid indexing, and we expect it to be more popular for that reason.