Yamaha Bolt, Button Head - 90111-08047-00. High-Quality Bolt for Secure Fastening of Yamaha Components. The Yamaha Bolt, Button Head - 90111-08047-00 is a precision-engineered fastening solution designed to secure various engine components. Featuring a button-head design, this bolt provides a streamlined, low-profile fastening option without compromising on strength or reliability. Whether you are working on routine maintenance or repairs, this bolt is a must-have for keeping your Yamaha engine