## Namura NA-40007R Piston Rings 94.93mm - Reliability and Performance The Namura NA-40007R piston rings with a diameter of 94.93mm are a key component for optimal engine performance, efficiency, and durability. Often overlooked, piston rings play a fundamental role in sealing the combustion chamber and controlling oil consumption. Namura, known for high-quality motorcycle and scooter parts, offers rings designed for the specific requirements of each application. ### Materials and Construction The choice of materials for piston ring manufacturing is crucial for their performance. Namura uses carefully selected materials, such as ductile cast iron and stainless steel alloys, which are characterized by excellent wear resistance. Additionally, depending on the model, the rings may be coated with chrome, phosphate, or nitride, further increasing their durability and corrosion resistance. The type of cylinder sleeve, its coating, engine size, and stroke type (2- or 4-stroke) all influence the selection of the appropriate ring composition. ### Compression Rings Compression rings, made of ductile cast iron or stainless steel alloy, provide a tight seal for the combustion chamber, minimizing pressure loss and optimizing engine performance. Chrome, phosphate, or nitride coatings further enhance their wear resistance. ### Oil Control Rings Oil control rings consist of three components: two scraper rails made of ductile cast iron or stainless steel, coated with chrome, nitride, or phosphate, and a single expander ring made of stainless steel. This design effectively removes excess oil from the cylinder walls, preventing it from entering the combustion chamber and ensuring optimal lubrication. By choosing Namura NA-40007R piston rings, you are investing in quality and reliability, which translates to longer engine life and better performance for your motorcycle or scooter.