Yamaha - Shifter Gear Engagement Component 6K1-45641-01-00. Overview. The Yamaha Shifter 6K1-45641-01-00 is one of those parts that makes the difference between smooth gear changes and that clunky, unreliable feel nobody wants on the water. When it's working right, shifting into forward or reverse feels clean and solid. When it starts wearing out, you'll notice hesitation, grinding, or difficulty staying in gear. It's a key piece in keeping your lower unit shifting the way it should.. Key Features. • Precise Gear Engagement - Ensures smooth and accurate shifting between forward, neutral, and reverse.. • OEM Fit Alignment - Designed to match Yamaha shift system geometry for proper operation.. • Durable Construction - Built to handle repeated shifting and drivetrain stress.. • Consistent Shift Response - Helps maintain reliable engagement under varying conditions.. Compatibility. Compatible with select Yamaha outboard engines using this shifter configuration.Commonly used in Yamaha lower