TOP END PISTON KIT VERTEX 47.46MM YAMAHA YZ85 02-18

Manufactured in Italy, Vertex pistons are the leading choice for replacement pistons worldwide. Trusted by OEMs such as KTM, Husqvarna, Beta, and Gas Gas, Vertex provides state-of-the-art, high-quality pistons for nearly any powersports application. The company's collaboration with factory race teams on piston design demonstrates their commitment to quality and affordability. Vertex piston kits include the piston, rings, wrist pin, and circlips. Each piston is heat-treated with a T-6 hardening and tempering cycle and features a molybdenum disulphide skirt coating to reduce wear and enhance the break-in phase. Forged Pistons for 4-Stroke Engines Four-stroke engines, with their higher cylinder pressures compared to two-strokes, require robust construction. Vertex’s four-stroke pistons are forged from high-quality 2618 aluminum alloy for superior strength and durability. Unique piston profiles and compression ratios, available in A, B, C, and D sizes, maximize power and performance while minimizing blow-by and oil consumption. Cast Pistons for 2-Stroke Engines - Cast pistons are ideal for two-stroke engines due to their higher silicon content, which is beneficial compared to forged pistons. Vertex pistons are gravity cast from an aluminum alloy with 18% silicon content. Silicon is crucial because: - It reduces thermal expansion, maintaining geometry after the piston reaches operating temperature. This allows for tighter tolerances compared to forged pistons, improving power and performance while reducing rattling and breaking. It enhances wear characteristics and prolongs piston life by minimizing wear on the piston skirt.