His crash ended a 1km pursuit along State Highway 1 that started near the Garvan Homestead and finished just south of Coe Rd.
The 24-year-old motorcyclist suffered moderate chest injuries and was taken by helicopter to Dunedin Hospital.
Acting Sergeant Andrew Denny, of Balclutha, said the incident began after reports of a motorcycle overtaking dangerously between Milton and Balclutha.
A police patrol car spotted the southbound motorcycle about 2.50pm. It was clocked at 148kmh, he said.
The police car turned to give chase, using lights and siren to encourage the man - later identified as a Christchurch electrician - to pull over.
The man did not stop and there was a short pursuit of about 1km, until the motorcycle failed to take a moderate bend, Acting Sgt Denny said.
The motorcyclist and his machine ended up in a ditch.
The man was having trouble breathing and was flown to Dunedin Hospital as a precaution.
He was likely to face charges of dangerous driving and failing to stop, Acting Sgt Denny said.
"It seems that his decision to fail to stop was his apprehension for speeding and the fact he did not have a motorcycle licence," he said in a statement.
No further details were available last night.
