Bicycle Torque Coupling

A special spanner is available for tightening and loosening the couplings.

Santana manufactures a "triplet (or quad) that can be transformed into a tandem by simply removing the center section of the frame.

"[3] The couplings are available in stainless steel, cromoly steel, and titanium and in different sizes, from 5⁄8 to 2 inches (16 to 51 mm) to match the frame tubing in which they are installed.

[4] They weigh about 8 oz (230 g) per pair, and arc as strong as uncoupled tubing.

[5] In order to support the ovalized tube Santana Cycles uses between the bottom bracket shells of their tandems, they have developed their own oval couplers.