3000W Gas Engine Generator, 7.5 HP Motor 4 Stroke Gas Powered Portable Generator. 3000W Gas Engine 7.5 HP Motor 4 Stroke Gas Powered Portable. Stroke: 70 55mm/2.76 2.17in. Stable Operation : It has a high-quality starter and cast iron cylinder liner, which makes the engine work stably and effectively to avoid jamming.