More than 500 cyclists from all over Westchester participated in a bike tour Sunday to raise money to find a cure for Multiple Sclerosis.Organizers say they raised more than $100,000 for the National MS Society. Cyclists rode from Tarrytown to Rockland State Park and back. The annual MS Bike Tour is the only time of the year when bicycles are allowed to cross over the Tappan Zee Bridge.MS is a neurological disease that affects the central nervous system. There is no cure for MS, but there are FDA-approved medications that slow down the course of the disease. Organizers of the bike tour say they hope their events will raise the money needed to find a cure for Multiple Sclerosis sooner than later.