Yamaha - Gear, ring - 6AW-81891-00-00Yamaha Ring Gear Lower Unit Gear System 6AW 81891 00 00 Overview Down inside the lower unit, the ring gear is doing the hard work of transferring power where it needs to go. When everythings dialed in, you get smooth rotation and solid push without thinking twice about it. But once wear starts or teeth get damaged, it shows up fastusually with noise or rough operation. This is one of those core components you trust to hold up when the engines putting