Michael Mosiman Bio
Michael Mosiman, born on 16 July 1999, is an American professional motocross and supercross racer from Sebastopol, California. He has competed professionally since his outdoor debut in 2017, racing in both the AMA Supercross Championship and the AMA Motocross Championship. Mosiman is best known for his victory at the San Diego round of the 2022 AMA Supercross Championship in the 250SX West class, his only supercross win to date. After multiple injuries that nearly ended his career, he returned to competition in 2025 riding for Monster Energy Star Racing Yamaha.
Early Life and Background
Michael Mosiman was born on 16 July 1999 in Sebastopol, California, and grew up in the United States surrounded by motorsports culture. He is the younger brother of Josh Mosiman, who has also competed in the AMA Motocross Championship, and that family connection played a major role in shaping his path into racing. Following his older brother into the sport, Mosiman progressed through the American amateur ranks on small-displacement machines, racing 85cc bikes and Supermini-class equipment during his early years.
During his amateur career, Mosiman was part of the Rockstar Suzuki Amateur Team, an arrangement that gave him structured support as he advanced. In 2013, he finished third in the Supermini class at the Monster Cup, a respected amateur showcase event. For his final two amateur seasons, he switched to KTM and Husqvarna machinery and earned a second-place finish along with two third-place results at the AMA Amateur National Motocross Championship, results that helped him earn a spot on a professional team.
Path to NASCAR
Michael Mosiman is not a NASCAR driver and has never competed in any of NASCAR’s national touring series. His professional career has been built entirely around two-wheel competition within the American Motorcyclist Association, including the AMA Supercross Championship and the AMA National Motocross Championship. As a result, the traditional NASCAR ladder system, regional touring divisions, and stock car categories do not apply to his background, and his path to professional racing was through the amateur motocross system described above.
Michael Mosiman Career
Early Career (2017-2018)
Mosiman made his professional debut in the 2017 AMA National Motocross Championship with the Rockstar Energy Husqvarna Factory Racing team. He adapted quickly to the 250 class, finishing eighth overall at the second round of the schedule. A shoulder injury at the fourth round forced him to miss the remainder of the championship, cutting his rookie outdoor campaign short. The following winter, he made his professional supercross debut in the 250SX East class of the 2018 AMA Supercross Championship but missed the first two rounds due to a concussion.
When healthy, Mosiman recorded a best finish of eighth and ended the 2018 supercross season fifteenth in the standings. Back outdoors for the 2018 AMA National Motocross Championship, he became a more consistent top-ten presence during the second half of the season and closed the year eleventh overall, establishing himself as a developing talent in the 250 class.
250SX and AMA Motocross Breakthrough (2019-2020)
Mosiman took a clear step forward in the 2019 AMA Supercross Championship, recording a best finish of fourth along with six other top-ten results and ending the year sixth in the final 250SX West standings. His progress carried into the 2019 AMA National Motocross Championship, where he captured his first career podium with a strong ride at the third round at Thunder Valley. He added two more top-three race finishes and several top-fives, finishing the outdoor series eighth overall.
The 2020 AMA Supercross Championship, shortened by the COVID-19 pandemic, saw Mosiman reach the podium for the first time in supercross with third-place finishes at the fourth and final rounds, closing the season fifth in 250SX West. A practice crash after the supercross season ended kept him out of the entire 2020 AMA National Motocross Championship, but he had already shown he could compete at the front of the 250 class.
Gas Gas Era (2021-2022)
For the 2021 season, Mosiman moved from Rockstar Husqvarna to the first factory Gas Gas squad in America. Racing in the 250SX East class, he added two more podiums and matched his previous supercross result by finishing fifth in the class standings. Outdoors, he matched his previous podium count and finished second overall at the sixth and eleventh rounds before a practice crash caused injuries that forced him to miss rounds eight and nine, ending the championship in eighth.
In 2022, Mosiman raced the 250SX West class of the AMA Supercross Championship and earned his breakthrough first win at the third round in San Diego, where he led every lap of the main event. He added four more podiums across the rest of the schedule and finished third in the final 250SX West standings. That summer, he secured his first outdoor race victory in the opening moto of the second round of the 2022 AMA National Motocross Championship, but a crash in the second moto and injuries in the second half of the season dropped him to ninth in the final outdoor standings. He also fractured his neck at the penultimate outdoor round that year.
Monster Energy Star Racing Yamaha Era (2024-Present)
After a difficult 2023 season that was cut short by a head injury at Daytona and a shoulder injury that required surgery, Mosiman was initially left without a ride for 2024. He eventually signed a multi-year deal with Monster Energy Star Racing Yamaha, returning to factory equipment and a top program. After riding only two rounds of the 2024 AMA Supercross Championship, a pre-season crash resulted in neck fractures. The severity of the injury led him to organize a retirement party, seemingly closing the book on his racing career.
Once doctors confirmed there was no further risk from the healed neck fractures, Mosiman returned to the starting gate for the 250SX West class of the 2025 AMA Supercross Championship. In his comeback season, he scored a podium at the fifth round in Arlington, Texas, and finished seventh in the final standings. He also recorded a single podium in the 2025 AMA National Motocross Championship before a crash at the penultimate round resulted in injuries and a concussion that forced him to miss the final event.
Driving Style and Strengths
Mosiman has shown particular strength on technical supercross tracks, where his smooth style and willingness to lead from the front were on full display during his wire-to-wire San Diego win. He works well with factory-supported programs, and his move to Monster Energy Star Racing Yamaha gave him access to top-level preparation and bike development. Across both supercross and motocross, his race craft has been defined by strong starts and the ability to convert front-running positions into podiums when his body has held up.
Notable Races and Milestones
His signature result remains the 2022 San Diego 250SX West main event, where he led every lap to claim his first and only supercross victory. He added a first outdoor race win at the second round of the 2022 AMA National Motocross Championship, plus a podium at Thunder Valley in 2019 that marked his first professional moto podium. His 2025 Arlington podium capped a comeback season that many had not expected after his neck fractures.
Michael Mosiman Career Wins
Michael Mosiman’s verified professional victories include one AMA Supercross Championship main event win and one AMA National Motocross Championship moto win, both coming during the 2022 season. Beyond those premier-class results, he has reached the podium on multiple occasions across both disciplines, including a podium at the 2025 Arlington round of the 250SX West class.
AMA Supercross Championship Highlights
Mosiman’s supercross win total stands at one, scored at the 2022 San Diego round in the 250SX West class. He has also added multiple podiums in 250SX competition, including third-place finishes during the 2020 season and four additional podiums during the 2022 250SX West campaign, which he ended third in the final standings. His most recent verified supercross podium came at the 2025 Arlington round in 250SX West.
Other Wins and Performances
In the AMA National Motocross Championship, Mosiman has one verified moto win from the opening race at the second round of the 2022 season. He has also reached the outdoor podium several times, including his first professional podium at the 2019 Thunder Valley round and additional podium finishes during the 2021 and 2025 outdoor seasons.
Michael Mosiman Family
Family Background and Racing Lineage
Michael Mosiman is the younger brother of Josh Mosiman, who has also competed in the AMA Motocross Championship. Following his older brother into the sport helped shape Michael’s early amateur career, and the two share a strong connection through motocross. That family link to racing was a major influence on his decision to pursue the sport professionally.
Personal Life
Michael Mosiman was born and raised in Sebastopol, California, and continues to be based in the United States. He is widely recognized for his resilience, having come back from multiple serious injuries, including neck fractures, to continue racing at the professional level.
2025 Season Performance
The 2025 season marked Michael Mosiman’s return to professional competition after neck fractures in 2024 had prompted a brief retirement. Racing the 250SX West class of the 2025 AMA Supercross Championship for Monster Energy Star Racing Yamaha, he delivered a strong comeback, highlighted by a podium finish at the fifth round in Arlington, Texas, and ended the year seventh in the final standings.
Carrying that momentum into the 2025 AMA National Motocross Championship, Mosiman added a single podium result across the outdoor schedule. His summer was cut short when a crash at the penultimate round caused injuries and a concussion, forcing him to miss the final event of the championship. Despite that setback, his 2025 campaign confirmed that he remained competitive at the front of the 250 class and gave him a clear platform to build on with Monster Energy Star Racing Yamaha.
