A motorcyclist was taken by Life Flight to Maine Medical Center after a crash in Harrison on Thursday night.

Emergency responders were dispatched to the area of Temple Hill Road around 5:40 p.m. for a report of an unconscious male on the roadway. The Cumberland County Sheriff’s Office says 26-year-old Zachary Emerson of Westbrook suffered a serious head injury in the crash. He was not wearing a helmet.

Police say Emerson had just done work on the motorcycle and took it for a test drive when he lost control for an unknown reason and was thrown on to the roadway. Speed and alcohol do not appear to be factors in the crash.

The crash is under investigation.

The sheriff’s office is reminding motorcyclists to wear a helmet.