List of Trans-AMA motocross champions
Trans-AMA champions

Year
Rider
Country
Machine
1970
Dave Nicoll
United Kingdom
BSA
1971
Sylvain Geboers
Belgium
Suzuki
1972
Åke Jonsson
Sweden
Maico
1973
Adolf Weil
West Germany
Maico
1974
Roger De Coster
Belgium
Suzuki
1975
Roger De Coster
Belgium
Suzuki
1976
Roger De Coster
Belgium
Suzuki
1977
Roger De Coster
Belgium
Suzuki
1978
Bob Hannah
United States
Yamaha

Question: Who won the most Trans-AMA motocross series and how many did they win?
Answer: Roger De Coster was a four-time winner of the Trans-AMA motocross series.