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Build Overview
This is Lynn’s custom gravel bike—a drop-bar Niner Air 9 mountain bike that we converted specifically for the Badlands Gravel Battle. The idea came from trying to make the downhills more comfortable and confidence-inspiring. Last time we raced Badlands, Lynn was braking on descents where the rest of us were letting the bikes fly. So the goal was simple: give her more control, more stability, and a setup that soaked up the rougher terrain.
The solution ended up being a super fun project: take her old hardtail mountain bike, add suspension with a Fox 32, mix in SRAM Force wireless road shifters, and combine it with a mountain drivetrain. Because SRAM AXS components can communicate across their road and mountain ecosystems, we were able to build something unique, practical, and fast without buying all-new parts.
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Full Build Specs
- Frame: Niner Air 9 (Small)
- Fork: Fox 32 suspension fork
- Drivetrain: Hybrid AXS system — SRAM Force drop-bar shifters + GX Eagle rear derailleur
- Rear Derailleur: SRAM GX Eagle AXS
- Cassette: SRAM Eagle 12-speed
- Crankset: SRAM Force carbon road crank (1x)
- Chainring: 38T (custom spaced using existing parts to achieve clearance)
- Handlebar: Easton AX aluminum drop bar
- Stem: 60mm (shortened from her MTB setup)
- Seatpost: (Used existing from MTB build)
- Saddle: Existing saddle from prior build
- Wheels – Everyday: Stock wheels from the Air 9
- Wheels – Race Setup: Carbon MTB wheelset from another bike
- Race Tires: Vittoria Mezcal / Barzo combination
Build Notes
This build started with a simple comment on a group ride: “You go how fast on the downhills?” Lynn had been braking on descents the rest of us were charging down, especially during the Badlands Gravel Battle. So we started brainstorming ways to help her feel more in control.
The answer was suspension. Instead of building a heavy adventure rig or buying something new, we realized we could repurpose her Small Niner Air 9 hardtail from the previous mountain bike season. Pair it with drop bars and AXS, and we’d get a gravel bike with MTB stability and road-style shifting.
We mixed parts we already had at the shop—something we enjoy doing. The drivetrain came partially from her carbon Warbird, which had SRAM Force AXS. Because SRAM’s wireless ecosystem works across road and mountain groups, we kept the Force shifters and paired them with a GX Eagle derailleur and a standard Eagle cassette. It shifts flawlessly and gives her massive climbing range.
The crank required some creativity. We originally tried a mountain crank, but it capped her top-end speed. Hearing Lynn say “my bike isn’t fast enough” is a rare moment of pride for the boys and me, so we put her Force carbon road crank on the bike instead. With some spacing and parts from older builds, we got a 38T ring to clear the frame. Ideally, she’d run a 40T, and after the race she said she probably could have pushed it.
To get the cockpit right, we used narrower-reach Easton AX bars and shortened the stem. Fit ended up being surprisingly good, though the stack is a bit tall (normal for MTB frames adapted to drop bars). The Fox 32 was the key confidence booster—taking the edge off rough terrain and making the fast downhills feel controlled instead of sketchy.
For everyday riding, she kept the stock wheels. For race day, we swapped in a carbon wheelset from one of our mountain bikes with Mezcal/Barzo tires, which worked really well. The combination of suspension, drop bars, and a wide-range Eagle drivetrain solved the original problem: Lynn was able to descend faster and more confidently at Badlands.
This build was a fun reminder that bikes don’t have to follow the rules. With AXS compatibility, a pile of parts in the shop, and a little creativity, you can come up with solutions that fit how you want to ride—even if they’re not something you can buy stock. And for riders who don’t see a perfect match in what’s on the floor, these projects are some of the most fun for us to build.
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