gravel bike bottom bracket Moots Routt 45 Titanium Gravel Frameset

The Moots Routt 45 Frameset comes from a shop that has been welding titanium in Steamboat Springs, Colorado since 1981. County Road 45 runs through Routt County — the road this frame is named for and one Moots' builders ride regularly. That's not backstory added for marketing texture; it's the context for why the Routt 45 exists: a gravel bike designed around what the terrain in that part of Colorado actually demands. Rocky, rutted, long, and unpredictable. The Routt 45 is built to handle all of it.

The geometry here is endurance-leaning rather than race-sharp. A longer top tube paired with a shorter stem puts the rider in a more upright position than a race-geometry gravel frame — confidence-inspiring on rough ground rather than aggressive. The head angle runs from 70.25 degrees in the smaller sizes to 71.5 in the 60cm, giving the bike a relaxed, stable front end when things get loose. Chainstay length holds at 437mm across all seven sizes (50 through 60cm), consistent handling character regardless of which frame you're on. The geometry is suited to covering real distance on real terrain.

The frame is built from Moots' 3/2.5 seamless titanium tubeset — thin-walled, US-made tubes in multiple diameters and wall thicknesses, tuned for ride quality at each individual frame size. The bottom bracket shell is 68mm English threaded, a standard that services easily and holds up without the creak issues that plague press-fit alternatives. Flat-mount disc brake mounts are 3D-printed in titanium, engineered for precise alignment between caliper, rotor, and axle. The rear end uses 142x12mm thru-axle spacing.

What the Frameset Includes

The Routt 45 ships as a complete frameset package: a Moots carbon gravel fork, a Chris King Inset 7 headset, a Chris King TF30 BSA 68mm bottom bracket, and titanium spacers. The Chris King components aren't filler — they're what most riders building at this level would specify regardless. Getting them standard means the frame arrives ready to build without sourcing a headset and bottom bracket separately, and both pieces service cleanly over years of use.

Tire Clearance and Mounting

Max tire clearance is 50c — wide enough for most gravel and mixed-surface applications, from fast-rolling file tread to more aggressive knobs for wet or loose conditions. Three bottle cage mounts give hydration range on long routes, a detail that matters on the remote back roads this frame is designed for. Fender eyelets at the lower legs and monostay chainstay bridge allow for all-season riding. The 27.2mm seatpost diameter is a traditional titanium spec that allows for a degree of vertical compliance not available through larger-diameter posts. Derailleur clamp is 34.9mm, compatible with 1x and 2x drivetrain configurations.

Finish Options

The Routt 45 is available in several finish configurations, reflected in the price range at RA Cycles. The base finish is Moots' natural brushed titanium — the look the brand is known for. Anodized/Etched and Premium finishes add color and visual treatment at additional cost. In 2026, Moots is offering a 45th Anniversary edition to mark over four decades of building in Steamboat Springs. Each option lets the rider shape the frame's aesthetic at the time of order, and all carry Moots' limited lifetime warranty.

Available in sizes 50 through 60cm, the Routt 45 frameset is the right foundation for a rider who wants to build something intentional — a titanium gravel platform that will outlast several component generations and still handle the same way a decade from now. This is what a considered gravel build starts with.