PISTON KIT 99-08 TRX XR 85.50, FORGED WOSSNER 8702D050 400
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Wossner forged piston kit with an 85.50mm bore. Manufactured in Germany, this high-performance piston enhances strength, heat transfer, and durability. The elliptical design ensures uniform bearing surface distribution, reducing localized pressure and preventing piston collapse. Features include forged construction for superior strength and durability, optimized heat transfer to cylinder walls, elliptical design for uniform bearing surface under heat expansion, and increased compression ratio for improved engine performance. Specifications: Bore 85.50mm (85.44mm actual), Display 397 cm³, Stroke 70.00mm, Clearance 0.06mm, Wossner Compression Ratio 12.50:1, OEM Compression Ratio 10.00:1, Dome Volume +8.40 cm³, Compression Height 26.20mm. Cross-reference OEM part numbers: Wossner Piston 8702D050, Lock CW20, Pin WP052, Ring Set 855XSY, Rod P4021.
- SKU
- 56-W4628_050.WO
- Brand
- Wossner
- Availability
- In Stock (1)
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 85.5mm
- Variant Id
- 255784
FULL DESCRIPTION
Wossner Forged Piston Kit 85.50mm for Honda TRX400EX/X
Upgrade your ATV's performance with this high-quality Wossner forged piston kit. Engineered for exceptional strength, durability, and heat transfer, this piston is manufactured in Germany to meet stringent quality standards. The advanced elliptical design ensures uniform bearing surface distribution under extreme conditions, reducing localized pressure and preventing piston collapse. Experience enhanced engine power and longevity with this premium upgrade.
Key Features:
- Forged construction for superior strength and resistance to wear.
- Optimized for efficient heat transfer to cylinder walls, promoting cooler engine operation.
- Elliptical piston design promotes even bearing surface distribution, even under thermal expansion.
- Increased compression ratio for noticeable improvements in engine performance.
- Precision manufactured in Germany.
Specifications:
- Piston Bore: 85.50mm (Actual bore: 85.44mm)
- Engine Displacement: 397 cm³
- Stroke: 70.00mm
- Piston to Cylinder Clearance: 0.06mm
- Wossner Compression Ratio: 12.50:1
- OEM Compression Ratio: 10.00:1
- Dome Volume: +8.40 cm³
- Compression Height: 26.20mm
Included Components:
- Wossner Piston: 8702D050
- Lock: CW20
- Pin: WP052
- Ring Set: 855XSY
- Rod: P4021
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