An afternoon motorcycle ride on rural roads in Lake and Napa counties turned into a search for a missing rider, later found badly injured in a crash, the CHP said.

Christopher Parlamento, 38, of South San Francisco, remained at Santa Rosa Memorial Hospital in critical condition, a hospital spokeswoman said Wednesday.

He had been riding Monday afternoon with friend Jeremy Piner when they became separated about 4:15 p.m. on Butts Canyon Road, CHP said. Piner began searching for his friend, going up and down the roads they had traveled. Unable to find him, Piner headed into Napa County and, with cell reception, called for help at 6:45 p.m.

CHP officers were alerted. Officer Shawn Bertram was on Butts Canyon Road near the Napa County line when he heard just before 7:30 p.m. someone calling for help. The officer found Parlamento off the roadway. He had crashed into a tree stump, suffering major injuries.

A medical helicopter carried Parlamento to the hospital.

The crash remained under investigation by Lake County CHP.

You can reach Staff Writer Randi Rossmann at 707‑521-5412 or randi.rossmann@pressdemocrat.com. On Twitter@rossmannreport.