FuelX Pro+ for KTM Adventure 390 (2020-2024)FuelX Pro+ for KTM Adventure 390 The all new FuelX Pro + is designed not just to offer you the best refinement and riding experience, but also improves part throttle horsepower and torque upto 25%. FuelX is a state of the art electronic plug in fuel injection optimizer for modern engines. It autotunes the engine to its best operational parameters, constantly monitoring, learning and adapting to the engines condition, wear and tear, riding style, add