Yamaha Woodruff Key YA0-05320-42-01. Overview. The Yamaha Woodruff Key YA0-05320-42-01 is a genuine original equipment manufacturer component designed to securely align and lock rotating parts within the engine assembly. This small but essential part ensures proper positioning between shafts and connected components, allowing for efficient power transfer and smooth mechanical operation.. Woodruff keys play a critical role in preventing slippage between mating parts such as gears, flywheels, or p