A 61-year-old man was seriously injured in a road accident on the A43 near Corby and was taken to hospital in Coventry by air ambulance.
The collision happened at about midday on Sunday (October 27).
A police spokesman said: “A black Volkswagen Golf, driven by a 43-year-old man from Swindon, was travelling north on the A43. As it turned right towards Bulwick, it was in collision with a yellow Suzuki motorcycle, ridden by a 61-year-old man from Stamford.”
The motorcyclist was taken to University Hospital Coventry.
Witnesses are asked to call the police on 101 or the Drivewatch Hotline on 0800 174615.