Yamaha recommends using Yamalube Full Synthetic Oil 10W-40 for their motorcycles, including the Yamaha FZ series. This oil is specifically formulated to meet the requirements of Yamaha engines and provides optimal performance and protection. It's always important to refer to the owner's manual or consult with a Yamaha authorized dealer to ensure you are using the recommended oil for your specific motorcycle model. They can provide you with the most accurate and up-to-date information on the recommended lubricants for your Yamaha FZ v.3.