Adds about 1-2hp and increased torque in excess of stock carb and is also fuel mixture adjustable. The 22mm is the appropriate alternative In case you are operating stock valves A Schrader valve performs according to a poppet system, though Presta valves do the job with a smaller sized diameter https://waylonzsjyl.onesmablog.com/helping-the-others-realize-the-advantages-of-engine-bike-50cc-75813423