Yamaha Gear Unit Assembly 7LY-13102-00-00. Overview. The Yamaha Gear Unit Assembly 7LY-13102-00-00 is a genuine original equipment manufacturer component designed to ensure smooth and efficient power transmission within your engine system. This gear unit assembly plays a critical role in transferring rotational force, supporting reliable operation and overall engine performance.. Engineered to Yamaha's exact specifications, this assembly provides a precise fit and seamless integration with your