Complex sentence: In 1919 the manufacturing rights were purchased by the Briggs & Stratton Company, who produced the Motor Wheel and Flyers until 1925, when they sold the Flyer to Automotive Electric Services Corporation.
Split into simpler sentences: In 1919 the manufacturing rights were purchased by the Briggs & Stratton Company, who produced the Motor Wheel and Flyers. In 1925, when they sold the rights to the Flyer to Automotive Electric Services Corporation.