This app provides, using temperature, altitude, humidity and atmospheric pressure values, a recommendation about the jetting configuration and spark plug to use for Rotax Max Senior, Supermax, DD2, Junior, Minimax or Micromax. In order to get the weather values, the application can use the location service (GPS or WiFi) to obtain the position and altitude, and the network connection to get the temperature, pressure and humidity from the nearest weather station. Nevertheless, the application can run without GPS, WiFi and internet connection, in this case, the user has to give the weather data.The application is made up of four tabs that are described next:- Results: in this tab, the recommended main jet, needle position and spark plug type values are shown. These data are calculated depending on the weather conditions and the engine configuration given in the next tabs. Under the recommended main jet, the calculated real value with decimals is shown. Besides this jetting information, the air density, density altitude and relative horsepower are shown too. In addition, this tab lets do a fine tunning adjustment to adapt to a concrete engine. We strongly advise you to adjust this value before the race in order to get an optimum performance. This value will be stored and used in the future sessions.- Weather: you can set the values for current temperature, pressure, altitude and humidity. The values of this screen can be manually set or can be loaded by the application reading the data from the nearest weather station (from the GPS tab).- Engine: you can set in this screen the information about the engine and the track, that is, the engine type (Senior, Junior, Minimax, Micromax, Supermax or DD2), the spark plug brand used, the needle type, the float/pilot jet combo, the float height, airbox type (new model or the old square model), track type (with long, short or medium straights), oil mix ratio and venturi type (12.5 or 8.5).- GPS: This tab allows to use the location service (using GPS or WiFi) to get the current position and altitude, and connect to an external service to get the weather conditions of the nearest weather station (temperature, pressure and humidity).The app let you use different measure units: C y F for temperatures, meter and feet for altitude, and mb, hPa, mmHg, inHg y atm for pressures.