The crash happened at around 4.35pm on Saturday (August 1) on the B3304 Porthleven Road in Helston. Cornwall Air Ambulance attended and flew a man, now known to the the motorcyclist, to hospital. A spokesperson for Devon and Cornwall Police said: "We are appealing for witnesses and dash-cam footage following a road traffic collision. "Emergency services attended the scene and the motorcyclist – a local man in his 70s – was taken to hospital with life-threatening injuries. "Anybody who witnessed the collision or who has relevant dash-cam footage, who has not yet spoken to police, is asked to call 101 or visit our website, quoting log 600 of August 1."