SupermotoUSA's next three races are all at the Simraceway Karting Center at Sonoma Raceway. All have Saturday Open Practice and Sunday racing. Anyone with a motorcycle that will pass tech and meets the track requirements is welcome for the Open Practice days. No pre-registration required. Sign up and pay at the track.
All three rounds will have use a different track layout. Round 3 is asphalt-only.
More info at: https://supermotousa.com/round-4-august-31-sept-1-sonoma/