The Transmission Assembly for 49CC two-cycle motocross bikes is designed to fit specific models: 40-5 and 40-6. This assembly includes various selectable tooth count options, ensuring optimal performance with your bike. It's crucial to have a well-matched and durable transmission for your 49CC motocross bike. This transmission assembly ensures smooth and efficient gear shifts, providing the perfect power transfer for every ride. With its robust build and adjustable options, it guarantees long-lasting performance and satisfaction.