Hold space to begin turning the flywheel, in turn kickstarting the engine. Move your cursor to the top of the screen to get options. Mode 1 is a perfect hit and miss Mode 2 has some misfires Mode 3 basically turns it into a throttle governed engine Throttle is the minimum speed before performing a power stroke. Load is simulating load on the engine. Carb Throttle is how much fuel can enter the engine