BILLINGS - A single motorcycle crash on Grand Avenue on Monday morning shut down traffic on a portion of the busy street.Police reported the accident shortly before 11 a.m. in the 1200 block of Grand Avenue.Eastbound traffic will be blocked off at 13th Street West and westbound traffic will be blocked off at 12th Street West, police said on social media. There will be substantial traffic delays so please avoid the area.The 62-year-old motorcycle rider was transported to a Billings hospital with serious injuries.