A quad rider catches some air during the Motocross spring series opener at Half Moon MX Park in Jacksonville, N.C. Many Marines with the II Marine Expeditionary Force headed out to the tracks to compete in the races. Motocross offers Marines a safe -and legal- alternative to street racing. - A quad rider catches some air during the Motocross spring series opener at Half Moon MX Park in Jacksonville, N.C. Many Marines with the II Marine Expeditionary Force headed out to the tracks to compete in the races. Motocross offers Marines a safe -and legal- alternative to street racing.