The Rotax MAX Jetting App enables the user to calculate the optimal carburetor main jet size for Rotax kart engines of the MAX series: - 125 Micro MAX evo - 125 Mini MAX evo - 125 Junior MAX evo - 125 Senior MAX evo - 125 MAX DD2 based on the current ambient conditions - Temperature - Altitude - Air pressure - Humidity This can be done either automatically using GPS and a functioning internet connection or manually by entering the ambient parameters. *Automatically* Click on Use GPS posit