Hayden Gillim grew up in Kentucky, racing flat track from the age of three. The cousin of Nicky, Tommy and Roger Lee Hayden, he got his first motorcycle for Christmas at age six and in that same year he went on to win his first championship at the Amateur Dirt Track Grand Championships. Gillim is currently atop the standings in the championship standings of Supersport with six top-three finishes, including a second place finish at Utah.