Newcastle and Lake Macquarie councils have been asked to improve road safety for bike riders after a study found more than three injured cyclists are admitted every week to the John Hunter Hospital.

University of Newcastle epidemiologist Ben Ewald interviewed more than 180 injured cyclists admitted to the John Hunter over a 12-month period, focussing on the two local government areas.

He found 84 of the accidents occurred on a road or cycleway, and 54 could not be determined from hospital records.

The report states safety issues were a major concern, including poor road or track surface, dangerous road structure, poorly designed kerb ramps and poor intersection design.

Dr Ewald, a bike rider himself, has forwarded the results to both councils and says some modification to some hazards is planned.

He says in Newcastle, the Roads and Maritime Service and local government are working to make cycling safer but get little information on the safety performance of their roads and bicycle facilities.