By Alex Evans

Published: Tuesday, 30 August 2022 at 12:00 am


A new SRAM prototype BlackBox direct-mount rear derailleur and all-new drivetrain were ridden by SRAM-sponsored riders at the 2022 Cross Country UCI Mountain Bike World Championships in Les Gets.

The new SRAM AXS electronic, wireless derailleur and drivetrain components were fitted to XCO gold medallist Nino Schurter’s Scott Spark RC, as well as being seen on other riders’ bikes from the Canyon, Specialized and Trek teams.

We managed to spot the new drivetrain components while at the World Championships in Les Gets and got a reasonably close look at the BlackBox kit.

Redesigning the derailleur

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Plenty of BlackBox components were buzzing about the pits.
Alex Evans / Our Media

Although it doesn’t look as though SRAM has torn up the rear-derailleur rule book with its latest BlackBox kit, because it still uses a cage with two pulley wheels that connects to the parallelogram-style body with a knuckle, the eagle-eyed will spot some important changes.

Most obviously, the new BlackBox derailleur no longer mounts to a derailleur hanger. Instead, its b-bolt (the term used for the main mounting bolt) appears to attach directly to the frame or axle at the dropout.

The derailleur features ‘loops’ that attach it to the bike, essentially sandwiching the frame at its mounting point.

Although we we weren’t able to remove the back wheel on any of the bikes we saw with the BlackBox kit, the derailleur appears to only be compatible with bikes using SRAM’s Universal Derailleur Hanger (UDH).

UDH launched in 2019 and was sold as a solution to the many different derailleur hangers on the market, where if one, single system was used spares would be easier to come by and derailleur setup and alignment should be easier and more accurate.

If it’s correct to assume the new derailleur’s body mounts directly to the bike’s frame, and from what we saw at the World Champs this is the case, clearly more was at play when SRAM announced the UDH nearly four years ago.

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The lower pulley wheel’s spokes appear to be made from metal.
Our Media

Continuing that line of thought, it appears the UDH was a mere placeholder for the brand’s new derailleur design, where the derailleur’s b-bolt ‘loop’ replaces the hanger entirely.

However, if the new derailleur does replace the UDH, it’s good news for owners of bikes that use a UDH, where upgrading to the new system should be possible.

Looking from the rear of the bike, the derailleur’s profile is slimmer than current, hanger-mounted systems, sitting further inboard.

By removing the hanger’s standard derailleur mounting position, everything looks further inboard than before, possibly reducing the chances of damage.

Arguably, the dual-sided ‘looped’ b-bolt mounting system looks more robust than current hanger-mounted derailleurs.

During the XCO race, gold medal finisher Nino Schurter put the new kit to the test as he crashed onto the bike’s driveside, skidding along the ground on one of the grassy turns that characterise the Les Gets course.

Crush for @nschurter ????

And he’s straight back on his bike!#LesGets2022 pic.twitter.com/jIG9mRLkM0

— UCI MTB (@UCI_MTB) August 28, 2022