Wayne Cornwell, 48, of Rensselaer, the driver and sole occupant, was pronounced dead at the scene, said Newton County Sheriff's Capt. Shannon Cothran.
Sheriff's deputies found Cornwell after responding about 5:32 p.m. to South County Road 525 East approaching East County Road 225 South for a report of a single-vehicle crash.
Cornwell was driving south on County Road 525 East when for unknown reasons he went off the road at an 'S' curve and was ejected from the motorcycle.
Police said Cornwell was not wearing a helmet when he crashed.