STURGIS, S.D. — A South Dakota saloon that billed itself as the “world’s largest biker bar” and was the subject of a reality TV show was destroyed early Tuesday by a fire that may have gained momentum when it hit an adjoining distillery containing 500 gallons of grain alcohol. Volunteer firefighters found heavy smoke when they responded to the Full Throttle Saloon in Sturgis around 12:30 a.m., and the main building was gutted less than three hours later. No injuries were reported. The bar, which featured such amenities as zip lines, musical stages and rental cabins, had been the subject...