This is Lynn’s custom gravel bike—a Niner AIR 9 RDO drop-bar mountain bike conversion built specifically to help her ride the Badlands Gravel Battle with more confidence on the downhills. We ride a lot of different setups, but this one is easily one of the most unique builds we’ve put together. Since it’s part of our Bikes We Ride series, we wanted to walk through how it came about, what parts we used, and how it rides.
Video review
History & setups we’ve tested
Races ridden on this bike:
- Badlands Gravel Battle
Wheelsets used:
- Stans Arch
- Reserve 28 XC w/ DT 350 hubs
Tires we’ve ridden:
- Vittoria Mezcal / Barzo
- Racing Ralph / Racing Ray
Drivetrain configurations:
- SRAM Force AXS Hoods and Brakes
- SRAM GX Eagle rear derailleur with Eagle 12-speed cassette
- SRAM Road Force with a 38T chainring
Photo gallery (optional):
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Drivetrain
This bike uses a mix of road and mountain components thanks to SRAM’s wireless compatibility. Lynn had been riding a carbon Warbird with Force AXS, so we built around that drivetrain and added a GX Eagle derailleur and Eagle 12-speed cassette. Everything works seamlessly together.
The bike originally had a mountain bike crank, but Lynn wanted more top-end speed. We swapped to her Force carbon road crank and paired it with a 38T chainring from an older RLT build. Chainring spacers fixed the chainline. It worked well—and after the race, Lynn said she could’ve pushed an even bigger ring on those descents.
Wheels and tires
For day-to-day riding, the bike uses the stock Niner MTB wheelset. For Badlands, we swapped to a set of carbon MTB wheels from another one of our bikes. Paired with Vittoria Mezcals, the setup rolled fast and added a lot of control and comfort on loose descents.
Cockpit and fit
The cockpit uses Easton AX50 aluminum drop bars and a shorter stem to get the reach right. Lynn had been running a 70–80mm stem on this frame as a mountain bike; we swapped to a 60mm for gravel geometry and drop-bar handling.
The stack is high, but the overall fit works for Lynn’s riding style and comfort goals—especially descending. This setup wasn’t built to be a race-geometry gravel bike. It was built for confidence, stability, and comfort, and it delivers exactly that.
Braking performance
The bike uses the stock SRAM G2 four-piston mountain bike brakes, and pairing them with the AXS shifters worked smoothly. Strong, predictable braking was important for Lynn’s confidence on the steep Badlands downhills, and this setup worked well.
Additional notes
The Fox 32 suspension fork played a huge role in this conversion—it smoothed out rough descents and helped Lynn stay relaxed rather than bracing for impacts. That added comfort was a big part of why she was able to descend faster than the previous year.
This build is also a good example of the kind of creative projects we enjoy. We try to reuse demo parts, swap components from former builds, and make modular setups that we can keep evolving. More and more, bikes leaving the shop aren’t staying stock. Even small changes like cockpits or wheels can make a big difference.
Final thoughts
This Niner AIR 9 RDO drop-bar mountain bike conversion turned out to be a great gravel bike for Lynn. The suspension fork, shorter cockpit, and mullet drivetrain all worked together to give her confidence on fast descents—exactly the goal of the build. It’s unique, fun, and surprisingly capable, and it was a great setup for the Badlands Gravel Battle.