PISTON KIT 98-99 YZF400 94.00, FORGED WOSSNER 8603D200
4.1 Trustpilot 99.9% positive on eBay
Free UK delivery 2–4 business days
Spread the cost with 
18+, T&Cs apply
Wossner 94mm Bore Piston Kit (Part No. 8603D200) is a high-performance forged piston designed for Yamaha YZ400F and WR400F models. It enhances heat transfer within the combustion chamber and features an elliptical design to ensure even load distribution, reducing localized pressure and preventing piston collapse. Manufactured in Germany, this piston maintains the OEM compression ratio for reliable engine performance. Features include high-strength forged piston construction, optimized heat transfer for improved combustion efficiency, elliptical design for even thrust load distribution, and manufacturing in Germany. Specifications: Bore Size 94mm, Actual Bore Diameter 93.95mm, Compression Ratio OEM 11.0:1, Displacement 290cc, Stroke 61.20mm, Clearance 0.06mm, Dome Volume -4.80cm³, Compression Height 23.00mm. Cross-Reference OEM Part Numbers: Lock P/N CW18, Pin P/N WP053, Ring Set P/N 940XSY.
- SKU
- 56-W4649_200.WO
- Brand
- Wossner
- Availability
- In Stock (2)
- General Product Group
- Engine
- General Product Type
- Pistons & Kits
- General Size
- 94mm
- Variant Id
- 255814
FULL DESCRIPTION
Wossner 94mm Bore Piston Kit
The Wossner 94mm Bore Piston Kit (Part No. 8603D200) is a high-performance forged piston designed for select Yamaha models. Engineered for superior strength and durability, this piston enhances heat transfer within the combustion chamber and features an elliptical design to ensure even load distribution, reducing localized pressure and preventing piston collapse. Manufactured in Germany, this piston maintains the OEM compression ratio for reliable engine performance.
Key Features:
- High-strength forged piston construction
- Optimized heat transfer for improved combustion efficiency
- Elliptical design for even thrust load distribution
- Manufactured in Germany
- Maintains OEM compression ratio
Specifications:
- Bore Size: 94mm
- Actual Bore Diameter: 93.95mm
- Compression Ratio: OEM
- OEM Compression Ratio: 11.0:1
- Displacement: 290cc
- Stroke: 61.20mm
- Clearance: 0.06mm
- Dome Volume: -4.80cm³
- Compression Height: 23.00mm
Included Components:
- Lock P/N: CW18
- Pin P/N: WP053
- Ring Set P/N: 940XSY
QUESTIONS? JUST ASK
Talk to John or Phil. Real people, Monday to Friday, 10:00 to 17:00.
Call or email us with your make, model and year and we will check it for you before you order.
UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. Delivery details
Yes. You have 14 days from delivery to return it, unused and in its original packaging. Contact us first and we will send you the return instructions. Returns policy
By card, PayPal, Apple Pay or Google Pay, or spread the cost with Klarna. Payment is taken securely by Stripe, and the options for your order are shown at checkout.
More answers in our FAQ.
Trade pricing available
Buying parts for your business? Apply for a 2BrosParts trade account.