If you have a tiny go kart that may have formally been powered by an electric motor, replacing the electric motor with a tiny gas motor is a fun way to get better performance out of your kart. You will lose torque by eliminating a DC motor, but you will also lose a lot of weight from the electric motor. Adding a tiny gas motor, like a weed-eater motor, will add range, decrease refueling time and provide an enjoyable alternative to the electric motor’s power.
Find and mark the sprocket that connects to the rear wheels. This is the same side the sprocket of the motor will go. Be sure your weed-eater motor will fit.
Take the shaft and cutter off of weed eater. Remove the hand-grip throttle control with the control wire/line and keep it intact for later use.
Remove plastic shrouding from the drive gear (where the shaft used to connect to the engine).
Connect the sprocket to the drive gear, making sure that the chain will clear the shroud and will allow the chain to connect to the wheel sprocket directly.
Place the weed-eater motor in position on the go kart frame. Use a metal strap to secure the motor. You want the sprocket of the weed-eater to line-up with the sprocket of the go kart precisely. If it’s off center, the chain will derail.
Connect the chain to both sprockets. Be sure there is a bit of flex (about ½ inch) in the chain.
Replace the go kart foot throttle with the weed-eater’s throttle lever.
Weed-eater motors are usually 19 – 25CCs, which is not very much to move a cart and human body. You will most likely have to assist the kart by providing initial momentum.
Be sure the weed-eater motor has no gas in it when you are welding.