A Ripon woman was seriously injured in a motorcycle crash in Fond du Lac County. The crash happened shortly after 9:30 pm Friday on Highway 23 and Rose Eld Road. A preliminary investigation shows a van operated by a 45 year old Fond du Lac woman failed to yield the right of way while making a turn in the intersection and collided with the motorcycle. A 50 year old Ripon woman was thrown from the motorcycle and flown by helicopter to a hospital with serious head injuries. The motorcycle operator, a 51 year old Green Lake man received minor injuries. The van driver and passenger were not injured. Both motorcycle occupants were not wearing helmets. Drivers of both vehicles were issued citations.