If you’ve been paying close attention, you’ve probably noticed that the hottest thing in mountain bike drivetrains for the last several years has been SRAM’s 1 x 11 system. Single-ring set-ups are, of course, nothing new to the sport. Factory 1X drivetrains have been used on downhill bikes for years, while cross-country racers and fit trail riders have been modifying their drivetrains for even longer. Time trial, triathletes, and ‘Cross racers have also been modifying their set-ups into 1X drivetrains for decades, but until last year’s release of the SRAM Force CX1 mini-group, there has never been a flawless, major brand, factory-spec, single ring drivetrain for road bikes based around a single chain ring. Now, the aforementioned Force CX1 will simply be known as Force 1, which will be SRAM’s premier road 1 x 11 system. A new Rival 1 group will provide a more affordable 1 x 11 option. Cyclocross racers, time trialists, crit specialists, monster ‘cross aficionados, and back roads gravel riders should be among the first to line up for SRAM’s newest release.
Most important are the new cassettes, which, yes, go to eleven. SRAM’s XG-1180 10-42 cassette pulls double-duty as both Rival 1’s and X1’s (MTB) eleven-cog stack, which has a three-cog machined “mini-block” structure and eight stamped, pinned cogs. Slightly heavier is the XG-1150, which serves in both Rival 1 and GX groups, and features eleven stamped, pinned cogs. If 10-42 seems like a bit of a stretch for your needs, or you don’t want to switch your hub’s freehub to the SRAM XD1 driver body, which both the 11-42 cassettes require, you have the option of an 11-36 eleven-cog cassette. Both the Force PG 1170 and Rival PG 1130 fit on current 10/11-speed freehub bodies.
New chainrings, featuring X-Sync profiling for unbelievable chain retention come in both compact 110 and standard 130 millimeter BCD dimensions. ‘Cross-size rings have extra clearance machined away from farther down the ‘ring from the teeth border, along mud evacuation routes scooped out at the base of the chainring teeth. Cranksets will come stock with removable 110 millimeter BCD spiders, which fit all but the 52/54 tooth rings. Aftermarket 130 BCD spiders will be readily available . Keeping the same Q-factor as 2x cranks, Force’s carbon arms and Rival’s forged alloy armed cranksets are available in both GXP (24mm) and BB30 (30mm) spindles.
Handling the cog changing duties are mechs based on SRAM’s X-Sync MTB derailleurs. Design on these derailleurs is nearly identical to the dirt versions, with the notable exception being the addition of a barrel adjuster. Short (28T), mid (36T), and long (42T) cage options are available depending on your cassette choice. Comparing the Force 1 and Rival 1 derailleurs, the major difference comes down to a stronger, more impact-resistant forged knuckle on the Force model, while the Rival sports a cost-saving cast knuckle.
Up front, the left side brake lever body has been modified from last year’s edition also. Previously, where the shifting mechanism was removed from the lever, a depression was palpable under the hood. New left-side levers have support where the depression used to be.