## Piston Rings 81.958mm Namura NA-80004R - Reliability and Performance for Your Engine The Namura NA-80004R piston rings with a diameter of 81.958mm are a key element in ensuring optimal performance, efficiency, and longevity of your engine. Often overlooked, these rings play a vital role in maintaining combustion chamber seal and proper lubrication. Namura, known for its high-quality motorcycle and scooter parts, designs its rings for specific applications, taking into account the type of cylinder liner, its coating, engine size, and stroke type (2 or 4-stroke). ### Advanced Materials and Technologies The materials used are one of the most important factors influencing the performance of piston rings. Namura uses highly ductile cast iron or stainless steel alloy, both characterized by excellent wear resistance and providing a tight seal. Additionally, depending on the model, chrome, phosphate, and nitride coatings are applied to meet the requirements of a specific engine. ### Compression Rings Compression rings, made of highly ductile cast iron or stainless steel alloy, ensure the tightness of the combustion chamber, minimizing compression losses and maximizing engine power. Chrome, nitride, or phosphate coatings further enhance their durability and wear resistance. ### Oil Rings Oil rings consist of three components: two scraper rails made of highly ductile cast iron or stainless steel alloy, coated with chrome, nitride, or phosphate, and a single expander ring made of stainless steel. Their role is to precisely dose the oil, ensuring proper cylinder lubrication and minimizing oil consumption. By choosing Namura NA-80004R piston rings, you are investing in the reliability and longevity of your engine.