PISTON KIT B 77MM YAMAHA YZ 250F 14-15, ATHENA S5F07700008B
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ATHENA Forged Piston Kit B, 77mm Bore Diameter (76.97 mm). This piston is made from a special high-performance aluminum alloy with high silicon content and is produced using cutting-edge CNC machining tools ensuring dimensional tolerances of less than 0.01 mm. Some piston skirts are treated with a molybdenum disulfide coating applied by screen printing to reduce friction. The piston rings are produced in Japan with wear-resistant coatings to increase retention and durability. This kit contains the piston, pin, circlips, and piston rings. Technical features include: Big End Pin Diameter 16x10x42 mm, Compression Height 20.40 mm, Compression Ratio 13.5:1, Displacement 250 cc, Net Weight 0.20 Kg, Number Of Segments 2, Piston Pin Type Standard, Piston Type Forged.
- SKU
- 56-W4961.B.ATH
- Brand
- Athena
- Availability
- In Stock (2)
Fitments (29)
| Make | Model | Year |
|---|---|---|
| YAMAHA | WR 250F | 2015 |
| YAMAHA | WR 250F | 2016 |
| YAMAHA | WR 250F | 2017 |
| YAMAHA | WR 250F | 2018 |
| YAMAHA | WR 250F | 2019 |
| YAMAHA | WRF 250 | 2014 |
| YAMAHA | WRF 250 | 2015 |
| YAMAHA | WRF 250 | 2016 |
| YAMAHA | WRF 250 | 2017 |
| YAMAHA | WRF 250 | 2018 |
| YAMAHA | YZ 250F | 2014 |
| YAMAHA | YZ 250F | 2015 |
| YAMAHA | YZ 250F | 2016 |
| YAMAHA | YZ 250F | 2017 |
| YAMAHA | YZ 250F | 2018 |
| YAMAHA | YZ 250FX | 2014 |
| YAMAHA | YZ 250FX | 2015 |
| YAMAHA | YZ 250FX | 2016 |
| YAMAHA | YZ 250FX | 2017 |
| YAMAHA | YZ 250FX | 2018 |
| YAMAHA | YZ 250FX | 2019 |
| YAMAHA | YZF 250 | 2014 |
| YAMAHA | YZF 250 | 2015 |
| YAMAHA | YZF X 250 | 2014 |
| YAMAHA | YZF X 250 | 2015 |
| YAMAHA | YZF X 250 | 2016 |
| YAMAHA | YZF X 250 | 2017 |
| YAMAHA | YZF X 250 | 2018 |
| YAMAHA | YZF X 250 | 2019 |
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 77mm
- Variant Id
- 289767
FULL DESCRIPTION
Athena Forged Piston Kit B - 77mm Bore
Enhance the performance and durability of your motorcycle with the Athena Forged Piston Kit B. Crafted from a special high-performance aluminum alloy with a high silicon content, these pistons are designed to meet or exceed Original Equipment (OE) standards, offering greater resistance and excellent performance for off-road applications.
Produced using cutting-edge CNC machining tools, Athena pistons achieve dimensional tolerances of less than 0.01 mm. The perfectly smooth piston profile promotes regular flow and optimal flame propagation. Some piston skirts feature a molybdenum disulfide coating applied via screen printing to further reduce friction, boosting performance and longevity.
Every Athena piston is engineered in Italy and rigorously tested on engine dynamometer benches and on the track to validate performance under extreme conditions. This piston kit includes the piston, pin, circlips, and piston rings. The piston rings are produced in Japan with wear-resistant coatings (PVD or chromium nitride) for increased retention and durability, ensuring they adapt perfectly to the cylinder liner even at low tangential loads.
Key Features:
- Forged piston for superior strength and performance.
- High silicon aluminum alloy for enhanced reliability and resistance.
- Precision CNC machining for tight tolerances (less than 0.01 mm).
- Smooth profile for improved airflow and flame propagation.
- Optional molybdenum disulfide coating on some skirts to reduce friction.
- Includes piston, pin, circlips, and piston rings.
- High-quality piston rings with wear-resistant coatings.
- Designed and tested by Athena R&D for extreme conditions.
Technical Specifications:
- Big End Pin Diameter: 16x10x42 mm
- Bore Diameter: 76.97 mm
- Compression Height: 20.40 mm
- Compression Ratio: 13.5:1
- Displacement: 250 cc
- Net Weight: 0.20 kg
- Number of Segments: 2
- Piston Pin Type: Standard
- Piston Type: Forged
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
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