Clem was considered for Led Zeppelin on a couple of occasions. He was initially on Jimmy Page's shortlist of drummers when forming the band, before they settled on John Bonham. Also at a later stage he was once asked to join Led Zeppelin for a brief spell in 1975 but turned down the offer.
Prior to this he had appeared alongside John Paul Jones on Donovan's hit single "The Hurdy Gurdy Man".