Racing fans outside Japan will know him for his regular wild card entries into international championships, primarily in the Japanese rounds. In the Superbike World Championship he entered between  and , taking a win in the Japanese round in , as well as three further podiums.
Outside of Japan, racing enthusiasts are familiar with his regular appearances as a wildcard competitor in international championships, especially during the Japanese events. In the Superbike World Championship, he competed from to , winning in the Japanese round and securing three more podium positions.