Police are now appealing for anyone who witnessed the incident which occurred around 7pm last night in the Grange Road area.
It involved a Yamaha VP 300 scooter and a white Renault Clio.
A 65-year-old man was taken by the Scottish Ambulance Service to Forth Valley Royal Hospital.
Sergeant David Marr from Forth Valley Road Policing said: “This was a serious road traffic collision in which a man suffered life threatening injuries and our investigation is ongoing to establish the full circumstances.
“We are appealing for anyone who may have witnessed the collision or have dash cam footage to get in touch to help officers with their investigation into what happened.
“Anyone with information can call Police Scotland on 101 quoting reference 3996 of October 28 or make a report anonymously through the charity Crimestoppers on 0800 555 111.”