The accident occurred at about 10:45 a.m. on Zaca Station Road, near Highway 154, said fire Capt. David Neel.
The cyclist was with a group of riders when a mechanical problem caused him to be thrown over the handlebars, Neel said.
The man, who was wearing a helmet, lost consciousness after the crash, he said.
The victim’s name, age and details on his condition were not available, Neel said.