How fast does a 6.5 hp engine run with 200 lbs?

The question cannot be answered directly with the provided information. You have provided the engine power in horsepower (hp) and the load weight in pounds (lbs). To determine the engine speed or revolutions per minute (RPM), you would need to consider factors such as engine design, gear ratio, and torque requirements. The relationship between engine power, load weight, and speed is determined through engine characteristics such as specific fuel consumption, torque curves, and displacement. Without this additional information, the exact engine speed cannot be quantified.