Fox + Son Jetmax vs Rotax Utility+

Precision jetting made easy — This app helps you calculate jetting for Rotax engines based on weather and altitude. Now every Rotax racer has access to the same jetting Fox + Son has used to power our engines to countless Rotax National wins and Grand Finals tickets. After many months of development and testing, we have successfully brought the same jetting algorithms we use on our dyno to a quick, easy-to-use app. We have also included all of our popular Rotax tuning tips that are found on our website, along with a handy interactive gear chart for your convenience. As we do with our website, we will continually update the app as we discover new tuning information. Anytime a new cylinder or part is introduced, all of the testing we do at the shop will flow directly to Jetmax. Jetmax will also calculate the relative horsepower for that atmospheric condition. The relative horsepower percentage is helpful information to have when selecting your gear ratio. In certain situations you can benefit from increasing your gear ratio when HP is low & decreasing your gear ratio when HP is high. Whether you're competing at the track or fine-tuning your kart for practice, Jetmax gives you accurate, reliable recommendations so you can focus on performance. Features: - Jetting calculator for Rotax engines - Calculates relative horsepower - Includes an interactive gearing chart Engineered by racers, for racers — Fox + Son Jetmax App delivers the tools you need to stay competitive on race day. *You must have a valid subscription in order to use this app.

Rotax Utility+ is the official mobile technical toolkit for Rotax karting. Designed for workshop, trackside and race-day use, the app brings Smart Jetting, Rotax E10 diagnostics and E10 scrutineering workflows together in one simple, efficient solution. Whether you are a driver, dealer, service center, scrutineer, race official or track operator, Rotax Utility+ helps you stay informed, make confident decisions and keep your focus where it belongs: on the track. SMART JETTING FOR ROTAX MAX ENGINES Stop guessing your carburetion setup. Smart Jetting calculates trusted main jet recommendations for Rotax MAX combustion engines based on current ambient conditions such as temperature and air pressure. • Use automatic weather input via your phone’s location or enter ambient parameters manually • Save jetting calculations together with weather data and personal notes • Build a reliable setup history to compare sessions and spot trends over time ROTAX E10 DIAGNOSTICS & ANALYTICS Turn your smartphone into a practical diagnostic dashboard for the Rotax E10 electric kart powertrain. Get a clear overview of key system information and track-relevant data directly in the paddock. • View general system information and current performance maps • Monitor Drive Unit status • Check battery State of Charge (SoC) and State of Health (SoH) • Read critical error codes and access actionable solution steps E10 SCRUTINEERING TOOLKIT Rotax Utility+ supports fast, precise and convenient technical inspections for professional race operations. The scrutineering feature is built to help officials verify compliance with confidence. • Read engine seal numbers, serial numbers and defined racing parameters • Receive alerts if irregularities are detected • Support paperless pre-race and post-race checks • Streamline official workflows using the required adapter cable and compatible dongle SIMPLE CONNECTION, CLEAR RESULTS Advanced E10 insights are easy to access with the right hardware. • Quick connection via Bluetooth • Easy-to-understand visual layouts • Clear, structured results you can trust Required hardware for E10 features: • Official Rotax diagnosis connector to OBD2 adapter cable, available through your local Rotax dealer • Compatible third-party OBD2 Bluetooth dongle Rotax Utility+ is a read-only solution. It allows users to view, verify and document information without flashing, programming or modifying any systems. It does not replace BUDS. The integrated Rotax Jetting functionality brings trusted jetting recommendations, diagnostics and scrutineering together in one mobile app. Rotax Utility+. Diagnosis and jetting. Mobile, simple, efficient.