41131-ZW1-B01 Pinion (12T) Gear - Overview. The 41131-ZW1-B01 Pinion (12T) Gear is a precise OEM component designed specifically for Honda marine engine systems. This 12-tooth gear plays a critical role in transmitting rotational force within the marine propulsion mechanism, ensuring smooth and efficient power delivery. Manufactured to meet Honda's exact factory specifications, this pinion gear guarantees seamless integration with existing parts, maintaining optimal performance and durability..