A motorcyclist hit a tree at Yellow Rock early on Saturday morning and is in a serious condition in Westmead Hospital.
About 3.20am on Saturday, January 6, emergency services were called to Yellow Rock Road following reports a motorcycle had left the road and crashed into a tree.
The 34-year-old rider of an unregistered KTM trail bike was found in a garden after the motorcycle left the road and travelled 15m into a tree, police said.
A friend of the rider following behind found the man and contacted emergency services.
He was treated at the scene by NSW Ambulance paramedics and airlifted in an induced coma to Westmead Hospital in a serious condition with injuries to his ribs, liver, lung and head.
The man was not wearing a helmet and it is being investigated if alcohol may have been a factor in the crash, police said.
Police are urging anyone with information in relation to this incident to call Crime Stoppers on 1800 333 000 or use the Crime Stoppers online reporting page: https://nsw.crimestoppers.com.au/.