Season
Episode
- Episode 1: Junior Vs. Senior Part 1
- Episode 2: Junior Vs. Senior - Part 2
- Episode 3: Go Daddy Part 1
- Episode 4: Go Daddy 2
- Episode 5: American Chopper Special
- Episode 6: Flowjet Bike 1
- Episode 7: Flowjet Bike 2
- Episode 8: HP Bike 1
- Episode 9: HP Bike 2
- Episode 10: Peavey Bike 1
- Episode 11: Peavey Bike 2
- Episode 12: Australia 1
- Episode 13: Australia 2
- Episode 14: Australia 3
- Episode 15: Intel 1
- Episode 16: Intel 2
- Episode 17: Byron Nelson 1
- Episode 18: Byron Nelson 2
- Episode 19: Silver State Choppers' Chopper 1
- Episode 20: Silver State Choppers' Chopper 2
- Episode 21: Iowa Farm Bureau Bike 1
- Episode 22: Iowa Farm Bureau Bike 2
American Chopper Season 4
Paul Teutul, Sr. and his son Paul Teutul, Jr. manufacture custom chopper-style motorcycles.
