He was with the
Jerry Garcia Band from 1983 until January 1994, when he was suddenly dismissed for reasons still unknown to him.[3] He went on to spend five years as Bob Dylan's drummer. Kemper joined Dutch
progressive rock band
Focus from 1975 to 1977, playing both on the Mother Focus album and tour. He has played with Mike Stinson,
Elkie Brooks,
Dennis Wilson (on the Bambu sessions) and
Bernie Leadon. He played double drums with
Jim Gordon on
Barry McGuire's "Don't Blame God" from his Lighten Up album in 1974.[4]