Yamaha - Ring Gear Engine Timing Component YF1-52626-38-20. Overview. When you're inside the geartrain on a Yamaha, everything has to mesh perfectly or you'll feel it right away. I've seen engines develop noise or timing issues just from worn gear teeth that don't look that bad at first glance. The Yamaha Ring Gear YF1-52626-38-20 is built to keep that rotation smooth and consistent where it matters most. It's one of those parts you don't want to cut corners on because it directly affects how th