A 28-year-old man has been airlifted to Canberra Hospital in a serious condition after he came off his motorcycle east of Yass on Tuesday morning.

One northbound lane on the Hume Highway at Jerrawa was closed after the crash which occurred at 5.40am, but has since reopened.

It is understood the man crashed down an embankment near Hillgrove Road.

The Snowy Hydro SouthCare helicopter transported the man in a stable but serious condition to Canberra hospital.

A spokeswoman for NSW Ambulance said the man suffered a suspected fractured arm.