SRAM has just dropped the most comprehensive component system for gravel riders yet, and I’ll get to the granular in a second. First, the head fake. SRAM calls the new system, XPLR, but they want don’t want you to pronounce that, “EX PEE EL ARE.” Their press release literally spells out at the top: “Say ‘Explore.’” Maybe there’s a good reason they didn’t just call it that? Is it too close to Explorer, which Ford kinda has the corner on?
Sorry, I’m not buying.
Drivetrains that begin with the letter X are the domain of their only competitor in the space, so pardon me if I think this is a sharp stick in the eye of Shimano.
Shimano launched GRX a few years back as a “dedicated” gravel group, and SRAM’s counter here is more comprehensive in several ways. Here’s that granular part you probably jumped directly to, anyway:
More Gears, and a Wider Spread
The macro message of the “Explore” group is choice. Lots of it.
That begins with being able to make some budget decisions, for instance, choosing Rival, Force, or Red level cranks, or mixing and matching per your wants from the parts bin. Translation: Rival is cheaper than Red in SRAM’s ecosystem, and you can mix Red and Rival, parts, so you don’t have to splurge on every part.
Another BIG deal is that XPLR allows a broader gear spread for gravel. As SRAM first did on the mountain side with Eagle cassettes that introduced single front chainrings mated to massive, 1-52 (520%) gear ranges, now they’re offering a 10-44-tooth, 12-speed cassette for XPLR mated to cranks in a huge range as well: 36, 38, 40, 42, 44, and 46-tooth.
If your brain already hurts at what’s going on here, a 1:1 ratio of front to rear is a good way to think about where gravel was before. GRX is offered as 1×11 with an 11-42 cassette and 42-tooth cranks, or 11-40 and and 40-tooth cranks: 40:40 or 42:42. A 1:1 ratio was a sort of golden mean on front-rear tooth setup for climbing on mountain bikes for years, but Eagle went way beyond and mountain bikers who rodeo up crazy steep climbs were thrilled. It allowed completely dumping the front derailleur, and XPLR is going that direction, hard.
While GRX still leaned heavily on 2x setups to get to that beyond 1:1 ratio, and a lot of “gravel” bikes came out of the box with 2x, riders who churn anything grimier than an even mix of dirt and pavement have long since switched over to 1x.
Enter an XPLR setup that’s well past 1:1, running a top cog of 44 and a smallest cog of 36 teeth. That may not be a SRAM Eagle combo of 52 teeth mated to a tiny 30-tooth granny, but you’ll find that kind of gearing on a trail or enduro rig that weighs (probably) a good ten pounds more than you svelte gravel machine.
The Twitter version: XPLR is giving you way more climbing mojo. But because you can also cook with, oh, a 44, or even a 46 front chainring, if you find yourself spun out on the flats, that 44 out back is going to allow a better balance between ascending churn and commuter mashing. Also: SRAM pushed the window on crank lengths, so short or tall riders can find their happier leverage ratio:
165mm, 167.5mm, 170mm, 172.5mm, 175mm, 177.5mm
Bonus: The whole shebang works with SRAM eTap, the Chicago brand’s wireless shifting system. I’ve dug eTap whenever I’ve tested it, in part because riders can program the levers themselves; Shimano’s wired Di2 not only requires routing those wires, but can only be programmed by a dealer.
Suspension, Front and Rear
Yeah, maybe you feel like you’re getting enough cush from your 50c tires, and a lot of gravel riders would prefer to shave weight than to add a fork to their dirt rigs. The Rockshox Rudy Ultimate fork, SRAM argues, gives gravel riders the chance for a short-travel fork that will also stiffen steering and throws riders of really long grinders a fatigue-fighting tool that could balance out the roughly one-pound penalty—give or take depending on the stock fork you’re running.
We’re talking about 40mm, or 1.5-inches of travel, which sounds like zilch, but hammer through a long descent of braking bumps with your triceps on fire and that could be enough to quell the meanness of your home turf and make the Rudy a game changer. This is definitely something I want to test, too, since in the endless search for the “one-bike-quiver” blurring the lines between the rigidity of a gravel bike (but the happiness of really light weight) and a very svelte, but expensive XC mountain bike makes me want to know if perhaps this helps get me closer to Goldilocks perfection.
That “rear” suspension part of the equation is actually…. the new Reverb Axis XPLR dropper seatpost. Not only does this activate via eTap, but SRAM built in a small amount of shock absorption here as well. Cleverly, that too, is rider adjustable. The minimum recommended pressure in the post is 200psi. Go lower, and you’ll get a softer ride. Amp the volume and you’ll sit on a firmer mattress. It’s not clear, and we won’t know before testing, if you can entirely eliminate all the motion, and also, how it rides if you want to go super-squish.
Wheels and Even Tires
Knowing that gravel riders like to roll on either 27.5 or 29er/700c wheels, SRAM, via Zipp, also crafted single-wall wheels for this category with a width designed to accommodate up to 50c tires. They’re claiming that their form of construction (single, rather than typical double wall rims for tubeless) enables a wheel that conforms better to the bumps and bruises of gravel riding, silly-puttying to the ground rather than forcing the tire to do all that work. That claimed compliance theoretically leads to fewer sealant burps, with both the rim and the tire rolling over sharper hits. Again, that’s a too-be-determined benefit.
SRAM, via Zipp, is also offering a gravel-specific tire. Here, I’m not sure what to think. It’s only offered in 40c, which is relatively narrow these days, and only in a 700c. Niche? Yep. The argument from SRAM is that they’re offering a tire with great durability, but there are plenty of tire choices for the segment, and tire choice is like saddle preference: Your personal “topography” should dictate what you roll.
As for the cost of all this kit, it varies from reasonable to…expensive…though you can also expect to see XPLR come as stock equipment across the gravel segment for new ’22 bikes. And we’ll have feedback on our own testing, soon.
Pricing includes controls (levers), chain, rear derailleur, cassette, rotors, bottom bracket, crankset, battery, and charger:
• SRAM RED eTap AXS Disc brake: $3,325
• Force eTap AXS Disc brake: $1,875
• Rival eTap AXS Disc brake: $1,237
• Zipp 101 XPLR wheelset: $1,800
• RockShox Rudy XPLR fork: $799
• RockShox Reverb XPLR seatpost: $600