[1][3] Sherwood first joined The Mothers of Invention as a roadie and equipment manager, also contributing sound effects (using both his voice and saxophone) to their first album, 1966's Freak Out!
He became a full member around the time of the group's experimental residence at the Garrick Theater in 1967, of which future bandmate Ruth Underwood, then an audience member, recalls that "there were some nights that you just heard pure music, and other nights, Motorhead'd be talking about fixing his car, with Jim Black's drum beat in the background".
Sherwood was one of several members that would play for him again in subsequent years, appearing on 1981's You Are What You Is, the Läther box set, and the last album Zappa completed before his death, Civilization Phaze III.
Ruben and the Jets toured in support of Zappa on the West Coast in 1972 and produced one other album, but split after lead singer Rubén Guevara was offered a solo recording contract in the mid-1970s.
[citation needed] The nickname "Motorhead" was coined by fellow Mothers member Ray Collins, who observed that Sherwood always seemed to be working on repairing cars, trucks or motorcycles, and joked that "it sounds like you've got a little motor in your head".