North Shore Local Area Command
About 4.30pm, a 44-year-old man was riding along Lady Game Drive at Lindfield when he attempted to avoid a car which had slowed to let a group of ducks cross the road and hit a vehicle travelling in the opposite direction.
The motorcyclist was taken to Royal North Shore Hospital for emergency surgery but was pronounced dead shortly before 7pm.
Lady Game Drive was closed in both directions for about 90 minutes as investigators from North Shore Local Area Command examined the scene.
The female driver of the other car was also taken to hospital for mandatory blood testing.
Police will prepare a report for the information of the Coroner.