Yamaha - Camshaft Gear Engine Timing Component YF1-52711-65-10. Overview. When you're working inside a Yamaha powerhead, timing is everything, and the camshaft gear is right at the center of that. I've seen engines run rough or lose power just from wear in the timing components, and it doesn't take much to throw things off. The Yamaha Camshaft Gear YF1-52711-65-10 keeps the camshaft and crankshaft working in sync so the engine runs smooth and efficient. It's not a part you replace often, but whe