PISTON KIT 14-15 YZF250 77.00, FORGED WOSSNER 8893DA, 1SM-11631-01-00
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This Wossner forged piston kit, part number 8893DA, features a standard 77mm bore with an actual piston size of 76.96mm. Manufactured in Germany, the piston is designed for high-performance four-stroke applications, offering superior heat transfer, strength, and pressure distribution due to its elliptical profile. Features include forged construction for strength and durability, an elliptical design for uniform expansion and thrust load balance, and optimized heat transfer. It is a direct OEM replacement and easy to install; professional installation is recommended if unsure. Specifications include a bore size of 77.00mm, actual piston size of 76.96mm, displacement of 249cm³, stroke of 53.60mm, clearance of 0.05mm, dome volume of -3.00cm³, Wossner compression ratio of 13.70:1, OEM compression ratio of 13.50:1, and compression height of 20.20mm. Cross-reference OEM part numbers include 40116M07700, 1SM-11631-01-00, CW16, WP087, and 770XAS-2.
- SKU
- 56-W4961.A.WO
- Brand
- Wossner
- 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
- 256476
FULL DESCRIPTION
Wossner Forged Piston Kit 77.00mm Bore
This high-performance Wossner forged piston kit is engineered for power and durability. Manufactured in Germany, this piston is designed to offer superior heat transfer, strength, and improved pressure distribution for demanding four-stroke applications.
Key Features:
- Forged Construction: Provides exceptional strength and longevity for high-performance engines.
- Elliptical Piston Design: Ensures uniform expansion and balances thrust loads for smoother operation.
- Optimized Heat Transfer: Engineered to efficiently manage heat, crucial for preventing engine damage under stress.
- Precision Machining: Features a standard 77.00mm bore size with an actual piston measurement of 76.96mm for a precise fit.
- Made in Germany: Guarantees high-quality manufacturing standards.
- Direct Replacement: Designed to be a direct OEM replacement for ease of installation.
Specifications:
- Bore Size: 77.00mm
- Actual Piston Size: 76.96mm
- Displacement: 249cm³
- Stroke: 53.60mm
- Clearance: 0.05mm
- Dome Volume: -3.00cm³
- Wossner Compression Ratio: 13.70:1
- OEM Compression Ratio: 13.50:1
- Compression Height: 20.20mm
Cross-Reference OEM Part Numbers:
- 40116M07700
- 1SM-11631-01-00
- CW16 (Lock)
- WP087 (Pin)
- 770XAS-2 (Ring Set)
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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.
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