A 28-year-old man from Paignton was in hospital with 'critical' injuries after a crash at Kingsbridge.
Police are investigating the collision between a Harley Davidson motorcycle and a Mini Cooper on the A381 between Slade Cross and Stumpy Cross around 2pm on Saturday.
Police say the male rider of the motorcycle suffered a serious head injury and was taken to Derriford Hospital in Plymouth. He remains in intenstive care in a critical condition.
The driver of the Mini, a 23-year-old man from the Kingsbridge area, was uninjured in the collision.
Police are appealing for witnesses to the collision and are particularly keen to speak to anyone who saw two large motorcycles in the area at the time of the incident.
The road was closed for four hours while police carried out an investigation at the scene.
Anyone with information is asked to contact police on 101, quoting reference 433 of 02/02/13.