Dunker competed in speedway,
longtrack and
grasstrack racing. He competed in the first One World Longtrack
world championship Grand-Prix series in 1997 and won the title. Although Dunker was best known for longtrack he finished fifth in the
1987 Individual Speedway Junior European Championship final after winning his qualifying round and reached the final of the
1988 Speedway World Pairs Championship. Dunker died on 4 July 2024, at the age of 55. == World Longtrack Championship ==