Tech / Geometry
On this page, you'll find details on how Wabi frames are built, the thinking behind our frame design, and geometry specifications for every model and size.
FRAME MATERIALS
REYNOLDS 725 TIG-WELDED FRAMES
Our TIG-welded steel frames use Reynolds 725, a heat-treated chrome-molybdenum steel that combines high strength with the ride quality that makes lightweight steel such a great frame material. Butted tubing places material where strength is needed while reducing weight elsewhere, creating a frame that is light, responsive, and comfortable.
Each frame is TIG-welded by hand and carefully checked for alignment before leaving the factory. The steel fork uses butted chromoly blades brazed to an investment-cast crown. Fork tips and rear dropouts are precision investment-cast steel, with an integrated brazed seatpost clamp.
REYNOLDS 725 LUGGED FRAMES
Our lugged frames also use heat-treated Reynolds 725 chrome-molybdenum steel, but pair it with traditional brazed construction.
Each frame is built by hand using low-temperature brass brazing with investment-cast lugs and bottom bracket shell. This construction requires considerable skill and creates the clean, precise joints that define a traditional lugged steel frame.
The frames are built to our specifications in Taiwan by a manufacturer with decades of experience producing high-level brazed steel frames in Japan and Taiwan. Each frame is carefully checked for alignment before leaving the factory.
The steel fork uses tapered chromoly blades brazed to an investment-cast crown. Fork tips and rear dropouts are precision investment-cast steel, and the seatpost clamp is integrated into the seat lug.
COLUMBUS SPIRIT TIG-WELDED FRAMES
Our lightest steel frames use Columbus Spirit, a high-performance, triple-butted steel tubing designed to achieve exceptional strength with very thin tube walls. The result is a remarkably light steel frame with a lively, responsive ride.
Each frame is TIG-welded by hand and carefully checked for alignment before leaving the factory. These frames are paired with a lightweight carbon fiber fork with an aluminum steerer.
FRAME DESIGN
A great-riding bicycle starts with more than good tubing. Geometry determines how the rider fits the bike, how the bike handles, and ultimately how it feels on the road.
We design our frame geometry around two fundamental considerations: rider fit and handling.
Fit begins with the relationship between the rider's primary contact points. Seat tube angle, top tube length, and handlebar position all work together to create a riding position that is efficient, comfortable, and appropriate for the way the bike is intended to be ridden.
Handling is a balance between stability and responsiveness. Too much stability can make a bike feel slow and heavy to steer. Too little can make it nervous or twitchy. Our geometry is rooted in traditional road-racing design, adapted specifically for fixed-gear and single-speed riding to provide quick, intuitive handling without sacrificing stability or comfort.
That balance is a defining part of the Wabi ride: responsive enough to feel lively in the city, stable enough to feel confident at speed, and comfortable enough for longer rides.
TESTING & MANUFACTURING
Frame design doesn't stop with geometry. Prototype frames are machine stress-tested before production, and our frames are manufactured and tested to applicable EN bicycle safety standards. Alignment and construction are carefully checked throughout production to ensure consistency and structural integrity.
Ultimately, tubing, geometry, construction, and components all contribute to how a bicycle rides. We focus on each of them because a lightweight steel bike should do more than look good on paper. It should feel balanced, responsive, comfortable, and simply enjoyable to ride.
FRAME GEOMETRY

IMPORTANT NOTE:
Prism frame sizes are measured differently from our Classic, Special, Lightning, and Thunder models.
Prism uses a center-to-top measurement, from the center of the bottom bracket to the top of the seat tube. Our other models use a center-to-center measurement.
Because of this, the size numbers aren't directly comparable. A 51cm Prism is equivalent in size to a 49cm in our other models, a 54cm Prism to a 52cm, and so on.
Prism Models
| 47cm | 51cm | 54cm | 57cm | 60cm | 62cm | ||
| Wheel size | 700C | 700C | 700C | 700C | 700C | 700C | |
| A | Seat Tube (c-t) | 470mm | 510mm | 540mm | 570mm | 600mm | 620mm |
| B | Effective Top Tube | 510mm | 530mm | 540mm | 550mm | 570mm | 580mm |
| C | Seat Angle | 75° | 74° | 74° | 73.5° | 73° | 73° |
| D | Head Angle | 70° | 71° | 71.5° | 72° | 72.5° | 73° |
| E | Fork Rake | 45mm | 45mm | 45mm | 45mm | 40mm | 40mm |
| F | BB Drop | 65mm | 62mm | 62mm | 62mm | 62mm | 62mm |
| G | Chain Stay (a) | 400mm | 400mm | 400mm | 400mm | 400mm | 400mm |
| H | Head Tube | 92mm | 92mm | 122mm | 150mm | 175mm | 194mm |
| J | Front Center | 582mm | 585mm | 592mm | 594mm | 600mm | 605mm |
| L | Wheelbase (c) | 988mm | 992mm | 1000mm | 1001mm | 1007mm | 1011mm |
| Standover (b) | 736mm | 750mm | 780mm | 807mm | 835mm | 854mm | |
| Stack | 484mm | 510mm | 530mm | 555mm | 580mm | 600mm | |
| Reach | 372mm | 375mm | 390mm | 380mm | 395mm | 395mm | |
| Default sizes | 47cm | 51cm | 54cm | 57cm | 60cm | 62cm | |
| Stem Length | 90mm | 90mm | 100mm | 110mm | 120mm | 120mm | |
| Road Bar Width | 400mm | 400mm | 420mm | 420mm | 440mm | 440mm | |
| Compact Bar Width | 400mm | 400mm | 400mm | 420mm | 420mm | 420mm | |
| Bullhorn Bar Width | 380mm | 380mm | 400mm | 400mm | 420mm | 420mm |
(a) Measured to front of dropout; (b) Measured with 35C tire (c) Measured from center of front and rear dropouts.
Classic, Special and Lightning Models
| 42cm | 45cm | 49cm | 52cm | 55cm | 58cm | 60cm | ||
| Wheel size | 650C | 700C | 700C | 700C | 700C | 700C | 700C | |
| A | Seat Tube (c-c) | 420mm | 450mm(a) | 490mm | 520mm | 550mm | 580mm | 600mm |
| B | Effective Top Tube | 500mm | 501mm | 530mm | 540mm | 550mm | 570mm | 580mm |
| C | Seat Angle | 73.5° | 75° | 74° | 74° | 73° | 73° | 73° |
| D | Head Angle | 71° | 70.5° | 72° | 72° | 73° | 73.5° | 74° |
| E | Fork Rake | 45mm | 45mm | 45mm | 45mm | 45mm | 40mm | 40mm |
| F | BB Drop | 40mm | 62mm | 62mm | 62mm | 62mm | 62mm | 62mm |
| G | Chain Stay | 375mm | 400mm | 400mm | 400mm | 400mm | 400mm | 400mm |
| H | Head Tube | 80mm | 85mm | 95mm | 125mm | 150mm | 176mm | 204mm |
| Standover (b) | 697mm | 725mm | 767mm | 796mm | 825mm | 854mm | 883mm | |
| Wheelbase | 910mm | 966mm | 975mm | 980mm | 980mm | 982mm | 985mm | |
| Stack | 430mm | 484mm | 510mm | 530mm | 555mm | 580mm | 600mm | |
| Reach | 380mm | 372mm | 375mm | 390mm | 380mm | 395mm | 395mm | |
| Default sizes | 42cm | 45cm | 49cm | 52cm | 55cm | 58cm | 60cm | |
| Stem Length | 90mm | 90mm | 90mm | 100mm | 110mm | 120mm | 120mm | |
| Road Bar Width | 400mm | 400mm | 400mm | 420mm | 420mm | 440mm | 440mm | |
| Compact Bar Width | 400mm | 400mm | 400mm | 400mm | 420mm | 420mm | 420mm | |
| Bullhorn Bar Width | 380mm | 380mm | 380mm | 400mm | 400mm | 420mm | 420mm |
(a) 45cm is center-to-top measurement; (b) Measured with 28C tires.
Thunder Models
| 49cm | 52cm | 55cm | 58cm | 60cm | ||
| A | Seat Tube | 490mm | 520mm | 550mm | 580mm | 600mm |
| B | Top Tube | 530mm | 540mm | 550mm | 570mm | 580mm |
| C | Seat Angle | 74° | 74° | 73° | 73° | 73° |
| D | Head Angle | 72° | 72° | 73° | 73.5° | 74° |
| E | Fork Rake | 50mm | 50mm | 50mm | 50mm | 50mm |
| F | BB Drop | 62mm | 62mm | 62mm | 62mm | 62mm |
| G | Chain Stay | 435mm | 435mm | 435mm | 435mm | 435mm |
| H | Head Tube | 92mm | 122mm | 147mm | 195mm | 202mm |
| Standover(a) | 770mm | 800mm | 825mm | 855mm | 880mm | |
| Wheelbase | 1010mm | 1020mm | 1020mm | 1030mm | 1040mm | |
| Stack | 510mm | 522mm | 560mm | 588mm | 625mm | |
| Reach | 375mm | 380mm | 385mm | 400mm | 405mm | |
| Default sizes | ||||||
| Stem Length | 90mm | 100mm | 110mm | 120mm | 120mm | |
| Road Bar Width | 400mm | 420mm | 420mm | 440mm | 440mm | |
| Compact Bar Width | 400mm | 400mm | 420mm | 420mm | 420mm | |
| Bullhorn Bar Width | 380mm | 400mm | 400mm | 420mm | 420mm |
(a) Measured with 35C tires.
