Every few years, drivetrain manufacturers add yet another cog to our bikes’ rear wheels in hopes of attracting dollars and market share. Chicago-based SRAM has kept pace with its competition, cog-wise, but the company has also worked on simplifying drivetrains by reducing the number of chainrings. SRAM’s 1x™ (pronounced one-by) movement began in their MTB category, where it was praised for its simplicity and security. In 2014 the company brought 1x technology to cyclocross with the introduction of the Force CX1™ group. And now, with the company’s announcement of their Force 1 and Rival 1 lines, SRAM brings the 1x option to road, gravel and adventure riding.
What Exactly Is 1x?
At the center of SRAM’s 1x drivetrain is the company’s X-SYNC™ single chainring. When combined with a wide-range cassette and dedicated clutch rear derailleur, the result is a secure, quiet system that offers a range of gears comparable to a traditional double-chainring (2x) setup. Benefits of the 1x drivetrain include less weight (approximately 175 gram savings), simpler shifting, fewer parts to maintain, and better chain control.
It’s important to note that SRAM is not abandoning the traditional double-chainring (2x) drivetrain. The company acknowledges that road 1x technology isn’t ideal for every application, and they remain committed to 2x drivetrains. The new Force 1 and Rival 1 groups complement their 2x counterparts by delivering increased chain control, simplified shifting, and reduced noise.
Is Less More?
You don’t need a PhD to figure out that a 2×11 drivetrain gives you twice as many gears as a 1×11 drivetrain. It’s obvious that 22 is more than 11, but what exactly do you give up if you switch to a 1x drivetrain? Having logged thousands of miles on SRAM’s WiFLi™ 2x drivetrains, I found myself asking that very same question when it came time to demo the company’s new road 1x groups.
SRAM’s WiFLi 2x drivetrains offer a staggeringly wide range of gears. The combination of a 50-34 crankset and 11-32 cassette have a range–or spread–of 428%. On mixed-surface (pavement, dirt, gravel) rides, I typically find myself using use most–if not all–of that range. Can a 1x setup offer the same range? In short, yes. By pairing a SRAM 44-tooth X-SYNC chainring with one of their 10-42 cassettes, the result is a gear range that covers more than 98% of the WiFLi 2x system’s range.
SRAM is expanding nearly all of its new 1x offerings into the renamed Rival 1 and Force 1 groups. Last year’s Force CX1 group is now known simply as SRAM Force 1. In addition to the aforementioned single-ring cranksets and chainrings, the new 1x Force and Rival groups include hydraulic and mechanical disc brakes, DoubleTap® (drop-bar) and trigger (flar-bar) shifters, 11-speed chains and cassettes, and rear derailleurs available in short, medium, and long cage versions.
When SRAM introduced the CX1 group last year, the X-SYNC chainring sizes were limited to 38 through 46 teeth (in two-tooth increments). The new Force 1 chainrings are offered in 38, 40, 42, 44, 46, 48, and 50-tooth sizes (110 mm BCD). For those riders who favor bigger gears, 52 and 54-tooth ‘rings will be available in 130 mm BCD (Rival 1 chainrings are only available in 110 mm BCD, in sizes 38 through 50-tooth). Both Rival and Force cranksets feature removable spiders. The Rival 1 (pictured below) and Force 1 X-SYNC chainrings share the same square-tooth design and wide-tooth undercut, but the Force 1 chainrings have additional beveled troughs designed to help shed mud and debris. All X-SYNC road chainrings are compatible with 130 and 135 mm rear spacing.
In a move that’s sure to bring a smile to gravel and adventure riders, SRAM is offering two 10-42, 11-speed cassettes for the Force 1 and Rival 1 groups. Both cassettes have the same cog sizes (10-12-14-16-18-21-24-28-32-36-42), but differ slightly in construction. The Force-level cassette (XG-1180) utilizes a mini-cluster design where the three smallest cogs are CNC-machined from a single piece of steel, whereas the Rival-level cassette (XG-1150) relies on the company’s Full Pin™ technology to hold the eleven cogs together. Both 10-42 cassettes require XD-compatible hubs or drivers.
SRAM’s 1x road derailleurs incorporate the same technologies from their MTB counterparts–namely, X-HORIZON™, ROLLER BEARING CLUCH™, CAGE LOCK™, and Exact Actuation™–but in a road specific-package, including the addition of a barrel adjuster. Short cage models are compatible with cogs up to 28T, mid-cage up to 36T cogs, and the new long-cage derailleurs are compatible with cogs up to 42T. If you’re not ready to take the plunge to 11-speed world, the Force 1 and Rival 1 rear derailleurs are also compatible with SRAM’s 10-speed cassettes and DoubleTap shifters.
Riding The 1x Setup
When SRAM invited me to their road 1x product roll-out, I assumed that I’d get some limited exposure to the new components, but there would be little in the way of hands-on testing. I was, to put it mildly, wrong. SRAM provided each journalist with two demo bikes that were outfitted with the new Force 1 and Rival 1 components. These weren’t just any demo bikes–each one was spec’d for the respective editor’s particular area of interest and expertise. My main ride was a Specialized AWOL Comp that had been kitted out with Rival 1 components, Zipp 30 Course wheels with Specialized 1.9″ tubeless knobbies, and finished off with Zipp Service Course handlebars, stem, and seatpost.
Our testing grounds were the roads and trails near Santa Margarita, California. SRAM scoped out a mixed-terrain route that would highlight the new components’ features and versatility. As such, the course included plenty of climbing and descending (see elevation profile below). Thanks to an early-morning storm, the unpaved sections ranged from peanut butter-esque mud to hero dirt. In other words, perfect testing conditions.
Having already logged more than 500 miles on SRAM’s CX1 group, I was really looking forward to trying the new road groups’ additional chainring and cassette options. At the same time, I wondered if the long-cage derailleur needed for the 10-42 cassette would shift as crisply on the smaller cogs. Any concerns that I may have had regarding the new systems’ shifting quality and performance were quickly erased. Whether shifting up or down the cassette, the Rival 1 setup never missed a shift (even when coated with mud and grime). Additional testing will obviously be required to assess long-term durability and performance, but based on past experience with the company’s CX1 components, I have high hopes for SRAM’s Force 1 and Rival 1 groups.
Disclosure: SRAM provided airfare and hotel accommodations, but offered no other form of compensation in exchange for editorial coverage.