SRAM XX SL Eagle AXS Transmission Bike

Inspired by the legendary Back 40 trail system, designed by our engineers, built entirely in our Bentonville factory – the BC40 is a modern racing machine that updates the XC playbook with the capabilities of an all-day trail sled. The bike’s 120mm suspension provides a second-to-none pedaling platform, and its progressive geometry delivers precise handling and tracking with stability at speed.

The BC40 wants to push watts through switchbacks and punch it over rolling singletrack. In the new SRAM Eagle XX SL, it’s found the ideal partner. SRAM’s Eagle transmission hinges on its axle-mounted derailleur, which sheds the noodly appendage of a derailleur hanger and anchors directly to the frame and cassette. The result is stiffer, more responsive shifting that lets you move the chain under extreme loads. It’s revolutionary, and it’s new, and it feels like no other derailleur we’ve shifted in anger.

XX SL is the lightest, most race-tuned version of Eagle. It looks the part, too, with lines so clean you almost hate to get it dirty. Almost. Direct-mount and lightweight don’t mean likely-to-break, though – the derailleur’s breakaway construction lets it disengage to, well, break away from impacts rather than breaking away from the frame.

XX SL’s narrower Q factor helps reduce that risk, situating the derailleur and crankset more inboard to avoid trail obstacles. It also self-adjusts, removing the greatest temptation of home mechanics: limit screws. We’ve succumbed to that siren song ourselves, thinking a slight tweak would do it, only to completely detune our shifting and end up in the shop, having an actual mechanic remedy our hubris. That’s less time waiting sheepishly at the bike shop and more time on the trail.

Engineered for the needs of the modern trail shredder. Built entirely in the Allied Technology Center. The BC40 is Made Here.

• Stretches the capabilities of what a cross-country bike can do while making no compromises with weight and pedaling efficiency. 
• Built with SRAM’s ultralight XC-racing transmission, the new Eagle XX SL
• In-house development with proprietary testing methodology and machines, with performance benchmarked against our competitors’ bikes.
• Every piece of carbon is meticulously cut, stacked, formed, and molded to hit the highest possible quality standard in our Allied Technology Center / Bentonville factory. 
• Aluminum suspension linkage and floating brake mount machined in-house to ensure the highest precision for fitment and alignment. 
• Built to exceed the expectations of multi-time Olympians and national champions, for ultimate performance at the highest level of competition.
• Inspired by decades of riding and racing, and purpose-built for the hundreds of miles of trails in our backyard.