Locate a spring adjustment governor at either the carburetor or sticking out of the differentials. The governor will look like a spring loaded device coordinated with the vehicle's accelerator.
Use the screwdriver to turn the bolts that hold the governor in place. Turning them clockwise will increase the tension, and turning them counter-clockwise will decrease the tension. Increasing the tension will increase vehicle speed, and decreasing the tension will decrease the vehicle's top speed.
Locate the cable nut that holds the cable to the throttle lever for a clutch cable governor. Adjust the main cable nut, holding it in place with the screwdriver. Turning the nut counter-clockwise will make the cable longer, allowing the cart to go faster. Turning the nut clockwise will reduce the vehicle's top speed.