It occurred at 10.30am on Sunday 7 August 2011, on the B1222 near Squires café and involved a red Aprilia 125 sports motorbike which was travelling from the old A1 towards Sherburn-in-Elmet and a black Vauxhall Corsa was heading in the opposite direction.
As a result of the collision the 37-year-old Harrogate man riding the motorcycle was taken to Leeds General Infirmary where he remains in a critical condition.
The woman driving the Vauxhall Corsa suffered minor injuries and was treated at the scene.
The road was closed for five hours following the collision.
Traffic Sergeant Sean Grey, of North Yorkshire Police’s Roads Policing Group, said: “This was a nasty collision which has left a man in hospital with serious and life changing injuries.
“I am appealing to anyone who witnessed this collision or saw the manner of driving of either vehicle prior to the incident to contact the police straight away.”
If you can assist with this investigation please contact TS Sean Grey at Tadcaster Police Station on 0845 60 60 24 7 quoting reference number 12110132419.