Riding test of the new Sram Red XPLR: 13 sprockets and no derailleur hanger

It has long been no secret that the component manufacturer from Chicago is working on a new, first-class groupset for off-road use. The first images of the Red XPLR AXS emerged around the Unbound event, which is regarded as the unofficial world championship for gravel bikers. Two months later, Sram has now officially confirmed the new drivetrain, which is described as the US company's "most advanced gravel groupset". This is made possible by a combination of road and MTB drivetrains.

Best of road bike and MTB drivetrains

With a mix of road and MTB drivetrains, the new groupset offers several advantages. The updated version of the almost eponymous top-of-the-range Red drivetrain contributes to improved shifting performance and impressive braking power, while the robust rear derailleur is taken over by the Eagle Transmission. In addition, the cassette uses 13 sprockets for the first time, which was previously a unique feature of Campagnolo's Ekar.

The new model offers some changes compared to the previous twelve-speed gearbox. An additional sprocket with 12 teeth has been added, and the largest sprocket now has 46 teeth instead of 44. This results in a gear range that is 20 per cent wider than that of a two-speed road groupset. This is despite the mono chainring that Sram has relied on since the introduction of the XPLR three years ago. Shimano currently only offers a two-speed version of the electronic twelve-speed GRX, while Campagnolo only offers mechanical versions of its two 1X13 groupsets. In addition, the three largest sprockets of the new 13-speed cassette are made of aluminium and are cushioned with foam to reduce noise.

A total of five different chainrings are available for the Red XPLR, which can be removed with a special tool when worn. Unlike the Red AXS, the optionally available power meter (€560) does not have to be replaced. However, the chainrings (170 euros) remain very expensive. The carbon crankarms are taken from the road groupset, although a new, short 160 millimetre version has been added.

Sram Red XPLR in figures

• Gears: 1x13
• Chainrings: 38, 40, 42, 44, 46 teeth
• Cassette: 10-46 teeth
• Price: 3960 Euro (without power meter), 4465 Euro (with power meter)
• Total weight: 2471 grams (weighed weight)

Familiar from MTB: The new gravel rear derailleur no longer has a derailleur hanger

In addition to the new 13-speed cassette, the Full-mount rear derailleur is the highlight of the new gravel groupset. Similar to the new MTB drivetrains, this is no longer attached to a derailleur hanger, but is instead attached directly to the thru axle with two aluminium brackets.

As already known from the Sram Eagle Transmission, this has two advantages: On the one hand, the new design makes the suspension more robust, and a so-called "magic wheel" on the lower derailleur pulley ensures that the chain keeps moving even if a small branch gets caught in it. On the other hand, the rear derailleur can be adjusted more easily and precisely without having to pay attention to end stops or the optimum distance to the sprocket set. According to Sram, the shifting performance remains constant after a single adjustment. With a little practice, the adjustment should take around ten minutes, with the in-house app guiding the user through the process.

Should damage occur in the event of a fall, spare parts are available separately. However, the rear derailleur is only compatible with frames that have a UDH interface. Sram introduced this standard in 2019 and it is becoming increasingly popular on gravel bikes and road bikes.

First practical test: Sram Red XPLR AXS

The Red XPLR fully convinced us in an initial practical test at the Sram development centre in Schweinfurt. The gears change quickly and precisely, even under full load, even if the noise level is slightly higher than with the road drivetrain. The lowest uphill gear (40-46) was hardly necessary, but we would have liked a slightly higher gear ratio on descents, although this can be easily adjusted with a larger chainring. The braking performance is impressive and works even better on uneven trails than on tarmac: the ergonomically shaped brake levers are easy to reach and allow you to trigger a powerful braking action with light finger pressure.

The new Sram Red weighs 2471 grams (weighed weight) and is initially only available in the high-priced top-of-the-range version. Without the power meter, it already costs 3960 euros. The individual parts are also very expensive; the cassette alone costs 657 euros (>> available here). However, it is expected that the US company will soon integrate the technology into more affordable models. According to information from our sister magazine TOUR, new XPLR versions of Force and Rival will follow next year. However, Sram did not want to comment on this when asked.

"You might also be interested in this": New wheels and tyres for gravel bikes

And what's more: In addition to the new Red XPLR gear system, Sram and its subsidiary Zipp are presenting further exclusive components for the Gavelbike. One highlight is the new 303 XPLR carbon wheels. Their unique selling point is a hookless rim in XXL format: thanks to the combination of a large rim width of 32 millimetres and a rim height of 54 millimetres, Zipp promises "the fastest gravel wheel ever". There are two versions to choose from: The lighter SW version costs 1800 euros and weighs 1607 grams according to our scales; the S version costs 1200 euros and is around 150 grams heavier.

The extreme rim profile is said to improve aerodynamic performance by five watts at average racing speeds. At higher speeds, which are less common off-road, the wheel benefits exponentially and can be up to ten watts faster at large angles of attack. The prerequisite for this is a 40 millimetre wide tyre, which - no surprise - Zipp has also included in its range.

Two Goodyear tyres in the range

The XPLR Slick (455 grams, 90 euros) was developed in collaboration with Goodyear, which continues the rim shape almost seamlessly and is mainly suitable for well-rolled gravel roads due to its smooth tread. We tested the slightly more profiled and wider XPLR Inter (525 grams, 90 euros). The 45-millimetre tyre rolls well and also ensures rapid progress on asphalt. However, the Goodyear tyre does not offer much lateral support when changing direction quickly on loose surfaces. As the wheels with reinforced rim flange allow low tyre pressure, the suspension comfort is very good. As a rule of thumb, Zipp recommends 0.5 bar less tyre pressure compared to similar combinations. In addition to Zipp's own tyres, around 25 tyre models will be compatible with the new hookless rims at market launch. An up-to-date list is available on the manufacturer's website and in the company's own app.