Born and raised in Suzuka, Japan, Shimoda began riding dirt bikes when he was 4 years old. After earning early success as an amateur racer in his home country, he sought out stiffer competition internationally. He competed in Europe (even racing against Jett Lawrence on occasion) and in the U.S., earning the 2016 Supermini 2 AMA Amateur National Championship at Loretta Lynn Ranch, at age 14. He signed with the Honda-supported Factory Connection team’s amateur program in 2017, then turned pro near the end of the 2019 season. In 2020 (Shimoda’s first full year as a professional), he finished third in the AMA 250SX East Region final standings, earning the AMA Supercross Rookie of the Year Award. With the Factory Connection team closing before the following season, Shimoda signed with Pro Circuit Kawasaki. In 2021 he became the first Japanese rider to win an AMA 250SX main event, finishing second in the East Region final standings. Last year saw him become the first Japanese rider to score an AMA Pro Motocross overall win, earning second in the 250 final standings. He was third in the same series earlier this year, also taking second in the inaugural SuperMotocross 250 class. So far in his career, Shimoda has collected three 250 overall wins in AMA Pro Motocross, one 250 Regional win in AMA Supercross and one 250 win in SuperMotocross.