31225-ZW1-004 Pinion Stopper Set - Overview. The 31225-ZW1-004 Pinion Stopper Set is a crucial component designed for Honda marine engine systems, ensuring proper engagement and reliable operation of the pinion gear within the marine drive system. This stopper set supports the mechanical functioning of the engine system by preventing unwanted pinion gear movement, which helps maintain smooth operation and optimal durability. Engineered to OEM factory standards, it ensures seamless integration wi