Dynojet, Thunderslide CV kit, US models Stage 1For US models; Stage 1. The Thunderslide for Harley Davidson has set a benchmark in jet kit design. It incorporates a custom made throttle slide of which the unique profile allows precise control over the slide''s range of movement. It creates a stronger signal; improving fuel atomizing which is essential for a good fuel burn. This provides more power; increased throttle response and improved fuel economy. **Dynojet product not available to purchase