Using this AS3 rear sprocket is straightforward. Just replace your old sprocket with this new one following the standard procedures for your Fantic motorcycle. When installing, make sure all the parts are properly aligned and tightened. As for maintenance, it's a good idea to clean the sprocket regularly, especially after riding on dirty or sandy tracks. You can use a mild cleaner and a soft brush to get rid of dirt and debris from the self - cleaning grooves. Also, check the sprocket for any signs of wear or damage frequently. If you notice any issues, contact the UK company that made it, as it comes with a 12 - month warranty. Keep in mind that this sprocket won't fit the XEF 250 Trail model, so double - check your motorcycle model before installation.