Emergency services have been called to a serious crash on Curletts Road involving a car and a motorcycle.

A St John spokesman told chrislynchmedia.com they were notified of the crash at 10.54 this morning and responded with an ambulance and a rapid response vehicle.

The crash happened between Lincoln Road and the Southern Motorway.

Fire and Emergency crews from Wigram Station also attended.

The motorcyclist was assessed at the scene and is being transported to Christchurch Hospital in a critical condition.

Motorists should expect delays while emergency services work to clear the road.

NZTA said State Highway 75 was closed between State Highway 76 and Lincoln Road to northbound traffic only.

Southbound lanes remain open.

Road users are advised to take extra when travelling along this route.