PISTON KIT A 85MM HONDA CRF 250 18-21, ATHENA S4F08500004A 289CC BIG BORE, KIT A
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ATHENA Forged Racing Piston Kit A for Athena Big Bore Cylinder, 85mm Bore Diameter, 289cc Displacement, 13.0:1 Compression Ratio. Includes piston, pin, circlips, and 2 piston rings with wear-resistant coatings. Piston features a special high-performance aluminum alloy with high silicon content and may have a molybdenum disulfide coating on the skirt to reduce friction. Manufactured with cutting-edge CNC machining tools ensuring dimensional tolerances of less than 0.01 mm. Big End Pin Diameter 16x40x9mm, Compression Height 18.92mm, Biconical Piston Pin Type. Intended for competitive use only.
- SKU
- 56-K197.85.PIS.A
- Brand
- Athena
- Availability
- In Stock (1)
Fitments (6)
| Make | Model | Year |
|---|---|---|
| HONDA | CRF 250R | 2018 |
| HONDA | CRF 250R | 2019 |
| HONDA | CRF 250R | 2020 |
| HONDA | CRF 250R | 2021 |
| HONDA | CRF 250R | 2022 |
| HONDA | CRF 250RX | 2019 |
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- Variant Id
- 295779
FULL DESCRIPTION
Athena Forged Racing Piston Kit A 85mm 289cc Big Bore
Upgrade your motorcycle's performance with this high-quality Athena Forged Racing Piston Kit. Engineered for superior reliability and power, this kit is designed to deliver exceptional results for demanding riders. Athena utilizes advanced manufacturing techniques and premium materials to ensure each piston meets the highest standards of quality and durability.
Key Features:
- Forged Construction: Made from a special high-performance aluminum alloy with a high silicon content for enhanced strength and resistance.
- Precision Machining: Produced using cutting-edge CNC machinery, guaranteeing dimensional tolerances of less than 0.01 mm for a perfect fit and optimal performance.
- Optimized Design: Features a smooth profile for regular airflow and perfect flame propagation, contributing to improved combustion efficiency.
- Reduced Friction: Some piston skirts are treated with a molybdenum disulfide coating to further reduce friction, boosting performance and extending durability.
- High-Quality Piston Rings: Rings are manufactured in Japan with wear-resistant coatings (PVD or chromium nitride) for increased durability and longevity. They are designed to adapt perfectly to the cylinder liner.
- Complete Kit: Includes the piston, piston pin, circlips, and piston rings. All components are replaceable and interchangeable.
- Engineered in Italy: Developed by Athena's R&D department and rigorously tested on dynamometer benches and on the track under extreme conditions.
Technical Specifications:
- Piston Type: Forged
- Bore Diameter: 85.00 mm
- Compression Height: 18.92 mm
- Compression Ratio: 13.0:1
- Displacement: 289 cc
- Number of Segments (Rings): 2
- Piston Pin Type: Biconical
- Big End Pin Diameter: 16x40x9 mm
Note: Products designed for increased displacement and power intended for competitive use are subject to specific regulations. Please ensure compliance with local road codes.
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