The 20-year-old from Colchester was riding a black Cagiva Raptor 125 motorbike when the bike was in collision with fencing and a wall in Robinson Road. It happened at 4.55pm on Friday July 8. He was riding along the road towards Red Barn Road.
The man was treated at the scene by paramedics before he was air lifted to the Royal London Hospital.
Police are investigating the circumstances leading up to the collision and are appealing for any witnesses or anyone with any information to come forward.
Anybody that can help is asked to contact Essex Police on 101.