American Custom Bicycles in Steel, Titanium and Ti/carbon mix

Seven’s Unique Chopped Chainstay Design

Five reasons this feature is so popular

  1. Super short chainstays: This is not a design goal in and of itself, but it can provide some excellent benefits for our riders, like superior agility and climbing capability as well as clearance for an even wider array of tire and chainring combinations.
  2. Stiffness: Building the stays out of tubes, rather the sheeted yokes or other shapes that designers have attempted, makes the rear of the bike stiffer as it resists flex in all directions.

    Our one-inch diameter titanium version of the chopped chainstays combined with our fastback dropout system provide a drivetrain that is twice as stiff as the most popular carbon race bikes we've tested.
  3. Big tires and any wheel size: One of the lessons of the last few seasons is that rider's want as much flexibility in tire and wheel choice as they can get from their bikes. The 2x2 bikes depend on our chopped chainstays to reach previously impossible wheel and tire combinations.
  4. Chainrings – all of them: You name it: 1x any size, double, even triple. We design around any and all gear combinations. Belt drives, too.
  5. Durability: Our tubular solution to the short stay conundrum provides the most durable, longest lasting drivetrain. Drivetrain solutions that rely on tubing rather than machined parts inherently have a higher fatigue strength.

For maximum durability we recommend our one-inch chainstays as they tend do be about twice as stiff and will therefore have more than twice the fatigue life, with all other variables being equal.

Visit our Chainstay Treatise page for details about why we recommend one chainstay type over another.