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SRAM has joined Shimano and Campagnolo with a dedicated gravel collection with its new XPLR set of parts. While the drivetrain isn’t a huge change — the levers, brakes, chain, and technology remain the same; only new 1x derailleurs and cassettes are added — the introduction of RockShox suspension and Zipp carbon wheels dedicated for gravel is big news and a leap over what Shimano and Campy are doing.
SRAM pronounces XPLR as explore not explorer.
What’s new at a glance:
- 3 1x derailleurs (Red, Force, Rival) designed for a 10-44 cassette
- 2 cassettes (Red and Force; 10-44t)
- RockShox Rudy XPLR fork (30mm and 40mm travel options)
- RockShox Reverb AXS XPLR dropper post (50mm and 75mm options, both 27.2mm)
- Zipp 101 XLPR wheels (15mm rim height; 1,665g claimed; 27mm internal width)
- Zipp G40 XPLR tires (rebadged from Tangente Course G40)
SRAM XPLR eTap AXS
SRAM’s wireless eTap AXS has been working just fine for gravel riding and racing, in both 1x and 2x configurations. But getting a wide-range 1x configuration has required mixing in mountain bike components, as the dedicated road rear derailleur and cassette had previously topped out with the 36t cog as the largest option.
SRAM’s Eagle AXS rear derailleur and cassette, by contrast, runs all the way up to a 10-52t option. (SRAM’s mechanical Force 1 group has a 10-42t cassette option.)
Now, SRAM has dedicated Red ($710), Force ($490), and Rival ($255) rear derailleurs built for 10-44t cassettes. They use the same pulleys as SRAM’s 2x derailleurs, and they are only compatible, SRAM says, with its Flattop chains. Weights range from 327g for Rival (without the battery) to 293g for the Red.
There are two cassette options: The $210 XG-1271 features an aluminum 44t cog for a 373g weight, and the $150 XG-1251 has a steel big cog that puts it at 412g. The steps on the 12-speed cassette are as follows: 10, 11, 13, 15, 17, 19, 21, 24, 28, 32, 38, and 44.
The cranks and chainrings for the XPLR group are slightly modified; the rings are now direct-mounted onto the spider. There are seven ring options from 38t to 46t, and the cranks come in wide versions, as well as a Quarq power meter option. Red cranks are $690, Force cranks are $420, and Rival cranks are not yet priced.
RockShox Rudy XPLR fork, Reverb AXS XPLR dropper post
While Shimano and Campagnolo have more experience with drivetrains than SRAM, neither owns a suspension brand like the Chicago-based company does. RockShox wasn’t exactly starting from scratch in building a gravel suspension fork and dropper post. In fact, both are longstanding products modified for gravel.
The $799 Rudy Ultimate XPLR fork uses RockShox’s Charger Race Day damper slimmed down for gravel with a lockout. The Rudy XPLR is an air-spring fork that comes in 30mm and 40mm travel options.
There is a single air chamber that can be set for a rider’s weight, and a rebound adjust tunes how quickly the fork springs back.
Zipp says the fork is designed to be supple for light chatter but is built with a big bottom-out bumper.
The XPLR weighs a claimed 1,230g. It has clearance for 50mm tires, includes fender mounts, and comes in two colors, two travel lengths (30mm and 40mm), and two offsets (45mm and 51mm).
The $600 Reverb AXS XPLR dropper post is actuated wirelessly by the AXS system. It can be programmed to work with any of SRAM’s wireless shifters, be those levers or satellite buttons. There are 50mm and 75mm-travel options, and 350mm and 400mm lengths.
A somewhat unusual feature of this post is that it also acts as a suspension post when not fully extended. Bodyweight moves the post down, and then unweighting the post and hitting the button or buttons pops it back up. When the post is anywhere in the range between fully extended and bottomed out, the post uses the air spring for suspension. RockShox calls this ActiveRide.
The air spring is set up to roughly double the rider’s weight, and inflate it with a shock pump connected at the bottom of the post.
The AXS XPLR dropper uses a battery that is interchangeable with a SRAM derailleur battery.
Zipp XPLR wheels and tires
Similar to SRAM’s drivetrains, Zipp wheels have been raced with great success in gravel for years, but the $1,800 101 XPLR is the first gravel-specific model from the Indianapolis-based wheel company.
“Our 303s are mostly designed for road; they just happen to be super capable for gravel and work well there,” said Zipp product manager Bastien Donzé.
Zipp’s team has spent some time investigating what makes wheels and tires fast on various surfaces. Aerodynamics and rolling resistance are two key factors, of course, but recently hysteresis has come to the fore for gravel.
“Vibration loss – hysteresis loss – that is the one that has us really interested. It is massive,” Donzé said. “I cannot state this loud enough: the amount of power you are losing from vibration on gravel is just mindblowing.”
Donzé said the Zipp team measured the XPLR 101 against another wheel with the same 28mm tires at 60psi and found a difference of about 40 watts on rough surfaces.
“Right now, these vibrations have nowhere to go,” he said. “If you film riders with slo-mo camera, you see all the vibrations on the muscles of the arms and the legs.”
So, Zipp built some lateral give into the rim of the 101 XPLR, which has a single wall instead of the box structure of most rims.
It’s a design borrowed from Zipp’s 303 Moto, where the rim can pivot laterally ever so slightly on the spokes. Donzé calls this ‘ankle compliance.’ The 101 XPLR uses the ZR1 hub with 66 points of engagement.
The 15mm deep rim has a 27mm internal width and builds into a 1,665g wheelset.
It comes in the same two colors as the RockShox Judy XPLR fork.
The wheels have a lifetime warranty, where Zipp will repair cracks or breaks for free.
Zipp has rebadged its Tangente Course G40 tubeless gravel tire as the G40 XPLR.
Finally, the Service Course SL-70 XPLR handlebar — the first SRAM product ever to tout the XPLR moniker when it launched in 2019 — continues on, now as part of the XPLR collection.