The size of the fuse used in a Yamaha FZ V2 may vary depending on the specific electrical system and model year. Typically, motorcycles use small blade-type fuses. However, to obtain the accurate and up-to-date information regarding the specific fuse size for the Yamaha FZ V2, it is recommended to consult the owner's manual of the motorcycle or contact a Yamaha dealership. The owner's manual will provide detailed information on the fuse specifications and locations for your particular model.