PISTON KIT 01-04 YZF250 77.00, FORGED WOSSNER 8559DA 3-RING, 5NL-11631-10-00
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Wossner forged piston kit 8559DA for Yamaha YZF250 models. Features a 77mm bore and 76.95mm size with a three-ring design. Manufactured in Germany, this piston is engineered to enhance heat transfer, ensuring uniform expansion and even thrust load distribution. The elliptical design prevents localized pressure and piston collapse, making it ideal for high-performance applications. Specifications include a bore of 77mm, size of 76.95mm, part number 8559DA, OEM compression ratio of 12.50:1, lock part number CW16, pin part number WP059, ring set part number 770XAS, displacement of 249 cm³, stroke of 53.6mm, clearance of 0.04mm, dome volume of -4.70 cm³, and compression height of 22.20mm. Cross-reference OEM part number 5NL-11631-10-00.
- SKU
- 56-W4738+00A.WO
- Brand
- Wossner
- Availability
- In Stock (3)
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 77mm
- Variant Id
- 256015
FULL DESCRIPTION
Wossner Forged Piston Kit 77.00mm for Yamaha YZF250 / WRF250
This high-performance forged piston kit from Wossner is engineered for durability and optimal engine performance. Designed with precision in Germany, it features a 77mm bore and a 76.95mm size, incorporating a robust three-ring design for enhanced sealing and power delivery.
The advanced design prioritizes superior heat transfer for uniform expansion and efficient thrust load distribution. Its elliptical piston shape actively prevents localized pressure points and potential piston collapse, making it an ideal upgrade for demanding riding conditions and high-performance applications.
Key Features:
- High-strength forged construction for exceptional durability.
- Optimized heat transfer for improved combustion efficiency and performance.
- Elliptical piston design minimizes localized pressure and prevents collapse.
- Three-ring configuration ensures superior sealing and optimal power output.
- Precision manufactured in Germany.
Specifications:
- Bore: 77mm
- Piston Size: 76.95mm
- Wossner Part Number: 8559DA
- Compression Ratio: OEM
- OEM Compression Ratio: 12.50:1
- Lock Pin Part Number: CW16
- Wrist Pin Part Number: WP059
- Ring Set Part Number: 770XAS
- Engine Displacement: 249 cm³
- Stroke: 53.6mm
- Piston Clearance: 0.04mm
- Dome Volume: -4.70 cm³
- Compression Height: 22.20mm
Cross-Reference OEM Part Number: 5NL-11631-10-00
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