The Athena Forged Piston Ø 81.95mm is designed for use with Athena Big Bore Cylinders, offering high durability and performance. Manufactured using reverse extrusion and precision CNC machining, it ensures dimensional tolerances of less than 0.01mm. Made from a high-performance aluminum alloy with a high silicon content, this piston provides excellent resistance and reliability comparable to OEM components. It features a smooth profile for optimal flame propagation and reduced friction, with molybdenum disulfide coating on some skirts for enhanced performance. The piston rings, produced in Japan with wear-resistant coatings, ensure minimal friction and increased durability.

Features

• Forged piston with an 81.95mm bore diameter


• High-performance aluminum alloy with high silicon content


• CNC-machined for precise tolerances under 0.01mm


• Molybdenum disulfide-coated skirts (on select pistons) for reduced friction


• Designed for use with Athena Big Bore Cylinders


• Piston rings with wear-resistant coatings for durability


• Includes piston, pin, circlips, and piston rings

Specifications

• Bore Diameter: 81.95mm


• Compression Height: 19.00mm


• Compression Ratio: 13.1:1


• Displacement: 280cc


• Net Weight: 0.23 kg


• Number of Segments: 2


• Piston Pin Diameter: 16x10x44.5mm


• Piston Type: Forged


• Piston Pin Type: Standard

Cross-Reference OEM Part Numbers

• Rings: S41316089

Vehicle Fitments

• Honda CRF250R (2004-2009)


• Honda CRF250X (2004-2015)