One person was seriously injured in a motorcycle crash in Fond du Lac County. The crash happened shortly after noon Saturday on Highway GGG near Forest Lake Road. A preliminary investigation indicates the motorcycle operator, a 54 year old Cedar Grove man, failed to negotiate a curve, lost control and traveled across the road striking a fence and several trees. He was not wearing a helmet. He was flown by helicopter to ThedaCare Regional Medical Center in Neenah with serious injuries. The crash remains under investigation.