PISTON KIT B 98MM YAMAHA YFZ 450 04-13, ATHENA S4F09800004B 478CC BIG BORE, KIT B
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ATHENA Forged Racing Piston Kit B, 98mm Bore Diameter, 478cc Displacement, 12.4:1 Compression Ratio. This kit includes piston, pin, circlips, and 3 piston rings. Features include a high-performance aluminum alloy with high silicon content, precision CNC machining for tolerances under 0.01 mm, and a perfectly smooth profile for optimal flow and flame propagation. Some skirts are treated with a molybdenum disulfide coating for reduced friction. Rings are produced in Japan with wear-resistant coatings. Big End Pin Diameter: 20x12x50mm. Piston Type: Forged. Piston Pin Type: Standard. Net Weight: 0.41 Kg. Part Number: S4F09800004B. Designed for Athena Big Bore cylinder kits. For competitive use only.
- SKU
- 56-K172.98.PKB
- Brand
- Athena
- Availability
- In Stock (5)
Fitments (57)
| Make | Model | Year |
|---|---|---|
| YAMAHA | YFZ 450 Bill Balance Edition | 2010 |
| YAMAHA | YFZ 450R | 2009 |
| YAMAHA | YFZ 450R | 2010 |
| YAMAHA | YFZ 450R | 2011 |
| YAMAHA | YFZ 450R | 2012 |
| YAMAHA | YFZ 450R | 2013 |
| YAMAHA | YFZ 450R | 2014 |
| YAMAHA | YFZ 450R | 2015 |
| YAMAHA | YFZ 450R | 2016 |
| YAMAHA | YFZ 450R | 2017 |
| YAMAHA | YFZ 450R Special Edition | 2010 |
| YAMAHA | YFZ 450R Special Edition | 2011 |
| YAMAHA | YFZ 450R Special Edition | 2012 |
| YAMAHA | YFZ 450R Special Edition | 2013 |
| YAMAHA | YFZ 450S | 2004 |
| YAMAHA | YFZ 450S | 2005 |
| YAMAHA | YFZ 450S | 2006 |
| YAMAHA | YFZ 450S | 2007 |
| YAMAHA | YFZ 450S | 2008 |
| YAMAHA | YFZ 450S | 2009 |
| YAMAHA | YFZ 450S | 2010 |
| YAMAHA | YFZ 450S | 2011 |
| YAMAHA | YFZ 450X | 2010 |
| YAMAHA | YFZ 450X | 2011 |
| YAMAHA | YFZ 450X Special Edition | 2011 |
| YAMAHA | YFZ BILL BALANCE EDITION 450 | 2010 |
| YAMAHA | YFZ R 450 | 2009 |
| YAMAHA | YFZ R 450 | 2010 |
| YAMAHA | YFZ R 450 | 2011 |
| YAMAHA | YFZ R 450 | 2012 |
| YAMAHA | YFZ R 450 | 2013 |
| YAMAHA | YFZ R 450 | 2014 |
| YAMAHA | YFZ R 450 | 2015 |
| YAMAHA | YFZ R 450 | 2016 |
| YAMAHA | YFZ R 450 | 2017 |
| YAMAHA | YFZ S 450 | 2004 |
| YAMAHA | YFZ S 450 | 2005 |
| YAMAHA | YFZ S 450 | 2006 |
| YAMAHA | YFZ S 450 | 2007 |
| YAMAHA | YFZ S 450 | 2008 |
| YAMAHA | YFZ S 450 | 2009 |
| YAMAHA | YFZ S 450 | 2010 |
| YAMAHA | YFZ S 450 | 2011 |
| YAMAHA | YFZ S 450 | 2012 |
| YAMAHA | YFZ S 450 | 2013 |
| YAMAHA | YFZ X 450 | 2010 |
| YAMAHA | YFZ X 450 | 2011 |
| YAMAHA | YFZ X 450 | 2012 |
| YAMAHA | YFZ X 450 | 2013 |
| YAMAHA | YFZ X 450 | 2014 |
| YAMAHA | YFZ X 450 | 2015 |
| YAMAHA | YFZ X 450 | 2016 |
| YAMAHA | YFZ X 450 | 2017 |
| YAMAHA | YFZ X 450 | 2018 |
| YAMAHA | YFZ X 450 | 2019 |
| YAMAHA | YFZ X 450 | 2020 |
| YAMAHA | YFZ X 450 | 2021 |
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 98mm
- Variant Id
- 253043
FULL DESCRIPTION
Athena Forged Racing Piston Kit B - 98mm Bore
Enhance your motorcycle's performance and reliability with the Athena Forged Racing Piston Kit B. Crafted by Athena, a leader in motorcycle spare parts for over 40 years, this piston is engineered for superior strength and durability.
Manufactured using cutting-edge CNC machining tools, this piston boasts dimensional tolerances of less than 0.01 mm. It's constructed from a special high-performance aluminum alloy with a high silicon content, ensuring OE-level reliability while offering increased resistance and excellent performance. The perfectly smooth profile promotes regular airflow and efficient flame propagation.
Some piston skirts feature a molybdenum disulfide coating applied by screen printing. This advanced treatment further reduces friction, boosting both performance and longevity.
Athena engineers are dedicated to providing advanced technical solutions and the highest quality standards, often exceeding original equipment (OE) production. Each piston is meticulously developed in Italy by the Athena R&D department, undergoing rigorous testing on engine dynamometer benches and on-track validation in extreme conditions.
This piston kit is designed for use with Athena Big Bore cylinder kits and includes piston rings engineered in Japan with wear-resistant coatings (PVD or chromium nitride). These rings minimize friction with the cylinder, leading to higher performance and increased durability. They are designed to adapt perfectly to the cylinder liner even at low tangential loads.
Kit Contents:
- Piston
- Pin
- Circlips
- Piston Rings
All components are replaceable and interchangeable.
Technical Features:
- Bore Diameter: 97.95 mm
- Compression Ratio: 12.4:1
- Displacement: 450 cc
- Number of Segments (Rings): 3
- Piston Type: Forged
- Big End Pin Diameter: 20x12x50 mm
- Piston Pin Type: Standard
- Net Weight: 0.41 Kg
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