The 401 gravel bike - lavender build in a grassy field

Gravel

The 401

Big Tires, Big Fun

401 Gravel

The Build

Your Dedicated Dirt Monster

A no-compromise gravel machine built for performance, no matter what that means to you. Nab podiums, cross expanses, or drop your friends on the group ride.

A mix of the best steel tubing money can buy and dialed-in geometry, with custom sizing to fit you like that pair of boots you should've thrown out.

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Design Details

Go Big or Go Home

The 401 gravel frame - full profile against a clear blue sky
01 - Tire Clearance

Built for Big Rubber and Big Rides

Clears 2.2" tires in all sizes. Built from day one to let you run the tires you want, not just the tires you can squeeze in. The front fork opens up tons of possibilities- dynamo wiring, racks, you name it.

The 401 gravel bike - full profile in a grassy field against an old barn wagon
02 - Sleek Lines

Go Fast, Look Good

Extensive use of 3D printing where it matters, and top spec Reynolds 853 where it doesn't. Fully parametric design means each bike is totally optimized for you. Custom UDH dropouts, T47 bottom bracket, and standard 27.2mm seatpost for maximum compatibility. 50T 1x chainring clearance just in case you're a beast.

Titanium bottle cages on the 401 down tube - Big Block script visible
03 - Make it Yours

Options Galore

A blank canvas so you can run whatcha brung. Mechanical shifting? Rack/bottle mounts? 2x? Suspension fork? Let's make it happen. If it's not listed, it's just because I haven't heard it yet- everything is on the table. Eccentric Bottom Bracket option for singlespeed builds is ready to go. Custom paint means anything from mild to wild aesthetics.

Brass Tacks

What It Costs

Starting at $2,500

What's included

  • Custom geometry frame
  • Paint-matched fork and thru axle
  • Custom Machined Big Block Seatpost Binder
  • Wheels Manufacturing Thru Axle
  • Two-color custom paint
  • Build Sheet with geometry, fit, and proposed component manifest

Here's your starting point. Pricing on high complexity multi-color paint jobs, extensive braze-ons, or changes to the build spec (suspension forks) are done case by case, but don't be afraid to ask! $500 deposit is due once geometry and manifest are developed and agreed upon. I will work with you on your goals for the whole build, including specifying all the necessary components, working with parts you have, etc. If you buy parts (stem, hubs, etc) to go with the bike, I'll paint match it to the frame!

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The Numbers

Specs & Geometry

Specifications

Frame MaterialReynolds 853, 3D-printed 17-4 Stainless Steel
Fork396mm Axle to Crown
HeadtubeIS52 - IS52
Bottom BracketT47 Internal - 85.5mm, Bushnell Eccentric Option for Singlespeed
ShiftingMechanical and Electronic
Seatpost Diameter27.2mm
Tire Clearance2.2" (57mm)
Rear Spacing12mm x 142mm Thru Axle
Brake Standard160mm flat mount
Derailleur HangerUDH
Crankset ClearanceStandard/Wide Q factors- 50T chainring maximum
FinishTwo color standard- paint matched parts if bought together

Geometry (mm unless noted)

Measurement Starting Point
Stackvaries
Reachvaries
Head Tube Angle71°
Seat Tube Angle74°
Chainstay435
BB Drop80

Ready to Ride?

Let's Get Crackin'

Every 401 is built to order, fit to your body, and finished to your vision. Reach out to start the conversation.

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