While the best rim brakes are powerful, lightweight and easy to operate, when a heavy tandem descends a steep grade the resulting heat build-up (up to four times that of a single bike) can blow-out a tire. Heat capacity, not stopping power, is why 20th-century tandems employed a drum brake. Unfortunately, because these simple “drag” brakes provided minimal stopping power, they couldn’t safely replace either rim brake. Consequently, decades of argument ensued as to the best way to operate three brakes. Lacking three arms, and never satisfied with the status quo, at Santana we dreamed of a lightweight disc powerful enough to replace a rim brake.