Principals of the firm were Manuel Calheiro Seixas, José Silvestre de Freitas and Augusto Maia. Production began in the 1930s in Lisbon, and they later moved to the premises now occupied by RTP.
Two machines were built, a 500 Turismo and 500 Sport, both powered by JAP engines driving through a Sturmey-Archer gearbox in the Sport and an Albion in the road model. They had Webb forks and rigid rear suspension.
The venture was not a great success and closed after just a few years, with total production quite low, perhaps only four units. Manuel Seixas moved to Brazil where he designed for the automobile firm Puma.
The SMC is the largest capacity motorcycle ever produced in Portugal. It features on a postage stamp from 2007, and a photograph of a restored example graces the cover of the book "Motos Antigas em Portugal".
Sources: Ribatejo Moto Clube; motosdoseculoxx.blogspot.com
