The Airtight Shop


Möbius Crit?

A Möbius Single Speed Criterium Frame is the fusion of a criterium frame and track frame.

Möbius Asymmetric Seat Stays are offset with the drive side lower.  Both stays connect to the seat tube and on to the top tube via a hand carved top tube lug.

This equates as less energy lost to frame flexing.   It is stiffer on the drive side so you get the power, while retaining a more comfortable ride in the saddle.

The Criterium/Track fusion means the frame has the tighter wheelbase of a track rear end, but the front end is criterium geometry with a greater bottom bracket drop for better balance. 

I basically wanted more power for a single speed that needs better handling for the mucked up city streets and traffic.

I usually like freewheel, but I have come around a bit to fixed gear.  The feeling of control as you are accelerating and decelerating is great! 

I believe these frames are beautiful (build and finish), but they aren't sculptural pieces alone.  They should be ridden hard!  If your frame isn't getting nicked up, you aren't using it!  

718.218.5667    |


One Man Shop.  

Built in Brooklyn.  

Custom Steel Frames Made to Order

All bicycle frames are tailor made to fit the rider's proportions and riding style.  

I'm a new builder with only a handful of frames under my belt, but with every frame I build, I'm shooting for my top level.  I ride and build single speeds mostly, so that is my focus.  My goal is to build very high performance frames that will be ridden in the city every day.  I consider single speeds perfect for the city, and love how they challenge your body to make up for more gears.

Everything is steel, bronze and silver. I hand miter the tubes and check my miters using Yamaguchi's traditional frame building techniques.  I hand shape the lugs and dropouts to get the function and aesthetic I want.  I love Campagnolo components, but I also use anything and everything that works well and fits the build.


Mathew Amonson                                   


Möbius Criterium Frame

Visits by Appointment Only

1205 Manhattan Ave,  Brooklyn NY 11222