Petaluma police suspect a motorcycle rider was intoxicated and possibly speeding Monday evening when he crashed and suffered major injuries.

Police Tuesday identified the man as Hank LaFranchi, 30, of Petaluma.

LaFranchi was heading north on Hopper Street about 6 p.m. when he lost control in a turn. Witnesses told traffic investigators the man appeared to have been speeding, police said. The bike left the road, hit a utility box and crossed railroad tracks before stopping in a field.

LaFranchi, who apparently wasn’t wearing a helmet, suffered serious injuries and was taken to Santa Rosa Memorial Hospital. Police said officers smelled alcohol and are investigating the crash as a possible DUI.

LaFranchi, who suffered major head injuries, was in stable condition Tuesday morning, police said.

Police closed Hopper Street, east of downtown Petaluma, near Lakeville Street and the Petaluma River, for about four hours Monday.

Officials asked anyone who saw the crash to contact Officer Mike Pierre at 707‑778‑4372.

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