A Lawrence man was hospitalized with a serious head injury on Monday afternoon, after losing control of his motorcycle near the Clinton Lake Dam.

Chas McElhinney, 72, was flown by helicopter ambulance to Kansas University Hospital in Kansas City, Kan., with critical injuries after the accident, at east 1000 Road and County Road 458. The man was not wearing a helmet, said Sgt. Steve Lewis, Douglas County Sheriff’s spokesman.

“He lost control for unknown reasons,” Lewis said. “He does not remember what happened.”

McElhinney was riding south on County Road 458, past Wakarusa School, when he crashed about 1:30 p.m. He was thrown from the motorcycle and hit his head on the pavement, said Lewis.

A previous version of this story had an incorrect age for McElhinney.