The collision occurred on the southbound carriageway of the A4260 dual carriageway at Duns Tew at about 6pm yesterday November 9.
Two vehicles were involved in this collision, a red Jeep Wrangler and a Honda motorcycle.
The rider of the Honda MSX Motorcycle, a man in his 20s suffered serious injuries and was taken to hospital.
Senior Investigating Officer, Sergeant James Surman, of the Roads Policing Unit, said: “We need the public’s help to aid our investigation to establish how the collision occurred.
“This incident happened during peak hours for commuting home, therefore it is possible there were a number of witnesses or people with dash cam footage.
“If you did witnesses the collision, if you have any footage or information then please contact Thames Valley Police via our website or call 101, quoting reference number 43210507212.”
