RockShox surprises with an aero-prototype SID: is aerodynamics coming to MTB?

The Leadville Trail 100 of 2025 left us with the incredible new record of Kate Courtney, the fifth victory of Keegan Swenson, or the confirmation that mountain bikes with road handlebars could become very common in a few years. But there was another great novelty in terms of equipment. There we saw for the first time a prototype RockShox SID Ultimate SL fork with aerodynamic attachments on the bottles.

RockShox's development department is testing an aerodynamic fork in competition

Some years ago, a study showed that an aerodynamic position on a mountain bike could save up to 23 minutes in a race like Leadville. And in that sense, the new prototypes that we have seen on Sofía Gómez Villafañe's Specialized Epic World Cup and Keegan Swenson's Santa Cruz Blur CC are heading in that direction.

 

 

 

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The Colorado race, with its 160 km full of fast tracks, is perfect for introducing aerodynamic innovations. And Black Box, RockShox's development department, has chosen this test to debut a striking SID Ultimate SL Aero equipped with "side fins" that we can imagine reduce air resistance in the long and fast sections of Leadville.

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From what we can see in the images, the fork really looks like a current RockShox SID Ultimate SL with the Flight Attendant system to which aerodynamic side attachments have been added, but it wouldn't be surprising if there were something more and it had some extra features imperceptible at first sight.

Will aero-MTB forks become common? It seems complicated, but it wouldn't be strange if they could be used in some races or stages of XCM where maintaining speed is key.