PISTON KIT 98MM YAMAHA YZ/WR 450 03-15, ATHENA S4F09800005A 478CC BIG BORE
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ATHENA Forged Racing Piston Ø 97.94 mm for Athena Big Bore Cylinder - S4F09800005A. This 450cc piston is crafted from a special high-performance aluminum alloy with high silicon content, ensuring OE-level reliability and enhanced resistance and performance. Produced with cutting-edge CNC machining tools, it features dimensional tolerances of less than 0.01 mm. Some piston skirts include a molybdenum disulfide coating applied by screen printing to reduce friction, further enhancing performance and durability. The piston rings are produced in Japan with wear-resistant coatings (PVD or chromium nitride) for increased lifespan and durability, adapting perfectly to the cylinder liner. This kit includes the piston, pin, circlips, and piston rings, all of which are replaceable and interchangeable. Technical features: Big End Pin Diameter 18x9x51 mm, Bore Diameter 97.94 mm, Compression Height 23.50 mm, Compression Ratio 12.4:1, Displacement 450 cc, Net Weight 0.39 Kg, Number Of Segments 2, Piston Pin Type Biconical, Piston Type Forged. All components are replaceable and interchangeable.
- SKU
- 56-K114_98.PIA
- Brand
- Athena
- Availability
- In Stock (1)
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 98mm
- Variant Id
- 298395
FULL DESCRIPTION
Athena Forged Big Bore Piston Kit 98mm
Upgrade your motorcycle's performance with this high-quality forged piston kit from Athena. Engineered for big bore applications, this kit is designed to deliver exceptional reliability and enhanced power output. Athena, a leader in motorcycle spare parts with over 40 years of experience, crafts these pistons using advanced CNC machining for precise 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 superior durability and performance compared to Original Equipment (OE) parts. The meticulously smooth profile promotes optimal airflow and efficient combustion, contributing to a noticeable performance improvement.
Some piston skirts feature a molybdenum disulfide coating applied via screen printing. This treatment further reduces friction, leading to enhanced performance and extended durability. Athena's commitment to quality is evident as each piston is engineered in Italy and rigorously tested on engine dynamometers and on track in extreme conditions to validate its performance and reliability.
This piston kit includes the piston, pin, circlips, and piston rings. The included piston rings are manufactured in Japan with wear-resistant coatings, such as PVD or chromium nitride, to maximize lifespan and ensure optimal performance by maintaining a precise fit against the cylinder liner, even under low tangential load.
Key Features:
- Forged piston for superior strength and performance.
- Precision manufactured with tolerances of less than 0.01 mm.
- High-performance aluminum alloy with high silicon content.
- Smooth piston profile for improved airflow and combustion.
- Optional molybdenum disulfide coating on skirts to reduce friction.
- Includes piston, pin, circlips, and high-quality Japanese piston rings.
- Engineered and tested for reliability in extreme conditions.
Technical Specifications:
- Piston Type: Forged
- Bore Diameter: 97.94 mm
- Compression Height: 23.50 mm
- Compression Ratio: 12.4:1
- Displacement: 450 cc
- Number Of Segments (Piston Rings): 2
- Piston Pin Type: Biconical
- Big End Pin Diameter: 18x9x51 mm
- Net Weight: 0.39 Kg
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