He also won a total of twelve C-1 medals at the ICF Canoe Sprint World Championships with seven golds (C-1 1000 m: 1985, 1989, 1990, 1991, 1993, 1994; C-1 10000 m: 1989), two silvers (C-1 1000 m: 1986, C-1 10000 m: 1991), and three bronzes (C-1 1000 m: 1987, 1995; C-1 10000 m: 1990). Klementjev's only non C-1 world championship medal was a silver in the C-2 500 m event in 1983.