Griffin, driver of the Rio, wore her seat belt and was not injured. A passenger in her vehicle, William T. Griffin, 43, also of Antioch, wore his seat belt and was not injured.
Clemmons was not injured. He also wore his seat belt.
Welker said Gross was wearing his helmet at the time of the accident.
He added that there was no indication that alcohol or drugs played a part in the accident, but that tests were still requested.