PISTON KIT B 77MM YAMAHA WR/YZ 250 16-22, ATHENA S5F07700009B
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ATHENA Forged Piston Kit B 77mm. Bore Diameter 76.96 mm. Compression Height 20.20 mm. Compression Ratio 13.5:1. Displacement 250cc. Piston Type Forged. Number Of Segments 2. Piston Pin Type Standard. Big End Pin Diameter 16x9.5x38 mm. Net Weight 0.18 Kg. Piston manufactured with a special high-performance aluminum alloy with high silicon content. Features include cutting-edge CNC machining for dimensional tolerances under 0.01 mm, molybdenum disulfide coating on some piston skirts to reduce friction, and piston rings produced in Japan with wear-resistant coatings (PVD or chromium nitride). Kit includes piston, pin, circlips, and piston rings. All components are replaceable and interchangeable. Products intended for competitive use are not subject to guarantee unless faulty.
- SKU
- 56-W4966.B.ATH
- Brand
- Athena
- Availability
- In Stock (4)
Fitments (15)
| Make | Model | Year |
|---|---|---|
| YAMAHA | WR 250F | 2018 |
| YAMAHA | WR 250F | 2019 |
| YAMAHA | WRF 250 | 2018 |
| YAMAHA | WRF 250 | 2019 |
| YAMAHA | YZ 250F | 2016 |
| YAMAHA | YZ 250F | 2017 |
| YAMAHA | YZ 250F | 2018 |
| YAMAHA | YZ 250FX | 2017 |
| YAMAHA | YZ 250FX | 2018 |
| YAMAHA | YZ 250FX | 2019 |
| YAMAHA | YZF 250 | 2016 |
| YAMAHA | YZF 250 | 2017 |
| YAMAHA | YZF 250 | 2018 |
| YAMAHA | YZF X 250 | 2017 |
| YAMAHA | YZF X 250 | 2018 |
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 77mm
- Variant Id
- 289768
FULL DESCRIPTION
Athena Forged Piston Kit - High Performance and Reliability
Upgrade your motorcycle's performance and reliability with this Athena Forged Piston Kit. Engineered in Italy, Athena is a leader in producing high-quality motorcycle spare parts with over 40 years of experience. This piston kit is designed for optimal performance in off-road applications.
Key Features:
- Forged Piston Construction: Made using a cutting-edge reverse extrusion process and advanced CNC machining for exceptional dimensional accuracy (tolerances less than 0.01 mm).
- High-Performance Alloy: Constructed from a special high-silicon aluminum alloy, offering superior resistance and performance while maintaining OE-level reliability.
- Optimized Profile: Features a smooth profile for regular flow and perfect flame propagation, enhancing combustion efficiency.
- Reduced Friction: Some piston skirts are treated with a molybdenum disulfide coating, applied via screen printing, to further reduce friction, boost performance, and increase durability.
- High-Quality Piston Rings: Rings are produced in Japan with wear-resistant coatings (PVD or chromium nitride) for increased durability and longevity. They ensure excellent cylinder liner adaptation even at low tangential load.
- Complete Kit: Includes piston, pin, circlips, and piston rings. All components are replaceable and interchangeable.
- Engineered for Performance: Rigorously tested on dynamometer benches and on the track under extreme conditions to validate performance and reliability.
Technical Specifications:
- Piston Type: Forged
- Bore Diameter: 76.96 mm
- Compression Height: 20.20 mm
- Compression Ratio: 13.5:1
- Displacement: 250 cc
- Number Of Segments: 2
- Piston Pin Type: Standard
- Big End Pin Diameter: 16x9.5x38 mm
- Net Weight: 0.18 Kg
QUESTIONS? JUST ASK
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Check the fitment table on this page against your make, model and year. Not sure? Call or email us and we will check it for you before you order.
Yes. We ship from the UK. Orders ship within 3 working days, then delivery to the United States takes 5–8 business days. The delivery price is shown at checkout before you pay. Delivery details
Yes. You have 14 days from delivery to return it, unused and in its original packaging. Contact us first and we will send you the return instructions. Returns policy
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