2024-08-26 00:00:00 Nº1 jetting App for Yamaha YZ 2T motocross bikes (2023 engines included) 1990-2023 models This app provides, using temperature, altitude, humidity, atmospheric pressure and your engine configuration and fuel type, a recommendation about best jetting (carburetor configuration) and spark plug to use for Yamaha 2-strokes MX bikes (YZ and PW models).