PISTON KIT A 98MM YAMAHA YFZ 450 04-13, ATHENA S4F09800004A 478CC BIG BORE, KIT A

Athena Forged Racing Piston Kit - Big Bore Upgrade

Enhance the performance and reliability of your engine with this premium Athena Forged Racing Piston Kit. Engineered with cutting-edge technology and high-quality materials, this kit is designed to deliver superior power and durability.

Athena, a leader in motorcycle spare parts for over 40 years, utilizes advanced reverse extrusion methods and state-of-the-art CNC machining to produce pistons with exceptional dimensional accuracy, ensuring tolerances of less than 0.01 mm. Constructed from a special high-performance aluminum alloy with a high silicon content, these pistons offer the reliability of original equipment while providing increased resistance and outstanding performance.

The pistons feature a perfectly smooth profile designed for optimal airflow and efficient flame propagation. Some piston skirts are further enhanced with a molybdenum disulfide coating applied via screen printing, significantly reducing friction to boost both performance and longevity.

Every Athena piston is meticulously engineered by their R&D department in Italy. Each unit undergoes rigorous testing on engine dynamometer benches under progressive stress loads and is validated on track in extreme conditions to guarantee performance and unwavering reliability.

This specific piston kit is designed for Athena Big Bore cylinder kits and includes high-quality piston rings manufactured in Japan with wear-resistant coatings (PVD or chromium nitride). These rings ensure minimal friction against the cylinder walls, leading to higher performance and increased durability. They are designed to perfectly adapt to the cylinder liner even under low tangential load.

Key Features:

• Forged piston construction for superior strength and performance.
• Special high-performance aluminum alloy with high silicon content.
• Ultra-precise CNC machining for tight tolerances (less than 0.01 mm).
• Optimized profile for smooth airflow and effective flame propagation.
• Optional molybdenum disulfide coating on skirts to reduce friction.
• High-quality piston rings made in Japan with wear-resistant coatings.
• Designed for Athena Big Bore cylinder kits.
• Kit includes piston, pin, circlips, and piston rings.
• All components are replaceable and interchangeable.

Technical Specifications:

• Bore Diameter: 97.94 mm
• Compression Ratio: 12.4:1
• Displacement: 450 cc
• Number Of Segments: 3
• Piston Pin Type: Standard
• Piston Type: Forged
• Big End Pin Diameter: 20x12x50 mm
• Net Weight: 0.41 Kg

Please note: Products designed for increased displacement and power beyond standard road regulations are intended exclusively for competitive use. Athena disclaims all responsibility for any use contrary to national regulations. Guarantees may not apply to products used in competitive sports or high-performance applications unless a clear faultiness is present.