Flying Horse 48cc/66cc/80cc 2-Stroke Motorized Bicycle Magneto Magnet &ndash; Gas Bike Magneto Flyweight Replacement The Magneto Magnet helps generate electrical current in your magneto loop set to give your 2-stroke 48cc or 66/80cc motorized bike engine spark To install, remove your magneto from the case. Unbolt the stock magnet and replace with the new magnet. Reinstall the magneto loop set, close the magneto case, and you're ready to ride