The Riva Stage 3 is FINALLY the biggest, baddest performance kit for your Ultra 310 on the market! At the heart of the entire kit lies the 3 pound boost pulley kit. This is delivering the necessary additional boost to make the horsepower you need to push this tank through the water. Reducing drag and getting the nose up more with the ride plate really ties this kit together. The BOV block off kit is required, as well as the Maptuner Nano to upload the tune for additional fuel and removal of the speed limiter. Riva recommends the 14/18 impeller to achieve the 80 MPH top speed of this kit. However, we are offering you a few alternative options that will also work as well. The stock prop can reach close to these speeds if you want to keep that. Otherwise, if speed isn’t your main goal, KP recommends re-pitching the stock prop to 15/22 or installing a Solas 15/22 impeller for INSANE acceleration. Top speed will be a few MPH less, but it will be insanely intense acceleration. Lastly, KP requires the fuel pump mod kit with this setup to prevent fuel starvation at WOT. The OEM fuel pump really struggles to put out appropriate fuel flow with the additional horsepower. One big key requirement of this kit is FRESH 93 Octane fuel at all times. Fuel that sits over 3w is not fresh, avoid full throttle operation or add a high quality octane booster. Putting fuel other than 93, can cause detonation resulting in permanent engine damage. For those of you who do not have 93 Octane, please contact Riva for a stage 3 tune that has stock ignition timing. Although slightly slower, it is safe. Safety is our goal for all you riders!