Motocross racing involves high speeds and rough terrain, including asphalt, gravel and dirt. This environment, along with complex race circuits, creates conditions that pose risk for head and brain injuries, including concussions. With the inclusion of a rotational energy component to safety certification criteria for motorcycle helmets, rotational mitigating technologies are present in some helmets, aimed at reducing the rotational motion transferred to the head. This study examined the influence of ground surface materials that could be found in motocross environments, on the head dynamic response, and the performance of a motocross helmet with and without rotational mitigating technology was evaluated. Surfaces of concrete with 80-grit paper, and mixed gravel, produced the highest head and brain response and were used to evaluate helmet performance. A Hybrid III headform with helmet was launched at 7.5 m/s at a 45° angle to front- and side-impact sites. Head linear and rotational acceleration and rotational velocity were measured, and THUMS was used to calculate the 95th maximum principal strain. Results showed that helmets with rotational technology reduced resulting head rotational components and strain to brain tissues. This study highlights the value of including rotational mitigating technology in motocross helmets to reduce the risk of injury.