The Silver Machine single was recorded live on this day in 1972 during HAWKWIND's set at the Greasy Truckers Party, The Roundhouse, London. Other artists playing that day were MAN, BRINSLEY SCHWARZ and MAGIC MICHAEL.
The original vocals were performed by Robert Calvert. The band considered them inadequate for the single, so an overdub was recorded by Lemmy.
They tried everybody singing it except me. Then, as a last shot, Douglas said, 'Try Lemmy'. And I did it in one take or two.
After overdubs and mixing, the single was released in June 1972.
An LP with selected tracks from every band at the Greasy Truckers Party was released in 1972. A 3CD boxset was compiled in 2007 with full sets from each band; including the original recording of "Silver Machine" with Robert Calvert's vocals.