For almost 10 years, Sram did not make any major leaps in development in the shifting segment for downhill bikes. But that's over now. For 2026, the Americans are adapting their hyped transmission shifting technology for the double bridge sector. Downhill racers have been waiting a long time for this step, as the T-Type wireless shifters allow precise, snappy shifting even under maximum load. If time is of the essence, this means that if you can shift gears faster when sprinting out of the start gate or on the home straight without taking the weight off the pedals, you save valuable tenths that often decide between the podium and a top 10 finish in the World Cup.
For the normal rider, the faster gear changes play a subordinate role. This is where the robust design of the direct mount rear derailleur shines: the defect-prone derailleur hanger is no longer required as it is mounted directly on the frame. But regardless of whether you are a racer or a hobby shredder - the DH Transmission provides noticeable added value for all gravity bikes, as it is more reliable, more robust and more precise than any other derailleur on the market.
With its virtually indestructible direct mount rear derailleur and the ability to shift precisely even under full load, the transmission technology seems predestined for downhill racers and park rats. It's all the more surprising that SRAM didn't take this step earlier. - Max Fuchs, BIKE test editor
The XX DH Transmission has a high price tag. Individual prices: € 765 for the rear derailleur, € 490 for the crank, € 545 for the cassette, € 112 for the chainring, € 150 for the chain, € 240 for the AXS Pod and around € 45 for the battery. Prices for the complete drivetrain are not yet known.
Indestructible: Direct mount rear derailleur for downhillers
The centrepiece of the DH Transmission is the radio-controlled 7-speed rear derailleur with the familiar direct mount of the T-Type platform. The frame must have a UDH derailleur hanger for mounting. The battery is well protected between the rear derailleur and chainstay - as with the GX AXS Transmission. The rear derailleur is narrower than usual and literally ducks under the chainstay. Together with the short cage, it offers hardly any surface to get caught on stones or roots. If the rear derailleur does hit something, no problem: the parallelogram and the cage itself are replaceable, as is a special skidplate - a plastic cover specially designed to keep bumps and scrapes away from the main components.
The Type 4 rear derailleur damper, familiar from the previous T-Type drivetrains, is at work inside. Thanks to the shorter cage and the shorter chain of the XX DH, the chain still sits much tighter than with classic 12-speed drivetrains.
More Sram and Rockshox news that might interest you:
XD-Slim: new cassette and freewheel standard
The 7-speed XD Slim cassette is also brand new. The narrower design moves the action radius of the rear derailleur and the brake further inwards to provide the best possible protection. At the same time, the system enables a symmetrical spoke angle for more stable wheels with even spoke tension. The only disadvantage: The Slim cassette is only compatible with the corresponding and also shorter Slim freehub body. This is therefore a completely new standard for downhill bikes.
Anyone converting or buying a new bike should therefore check exactly which hub is fitted and whether the rear triangle is compatible with the 148 millimetre wide SRAM standard. If you don't fancy a new standard, SRAM also has a "normal" 7-speed T-Type cassette in its range, which is compatible with all common hubs and XD freehubs.
High-end aluminium cranks and reinforced chainrings
Despite the XX label, the crankset uses aluminium instead of carbon in favour of durability. Available crank lengths: 150 to 165 mm millimetres. The chainring is equipped with reinforced teeth to prevent it from clipping and is available in sizes 32, 34 and 36 teeth.
Conclusion from Max Fuchs
With its virtually indestructible direct mount rear derailleur and the ability to shift precisely even under full load, the transmission technology seems predestined for downhill racers and park rats. It is therefore all the more surprising that SRAM did not take this step earlier. If the Americans add even more attractively priced variants in the future, the DH Transmission should establish itself as the new gold standard in the downhill segment in no time at all.
Max Fuchs
Editor
