Wossner 8169DB Piston Kit - KTM 250 SX/XC Husqvarna TC/TE Gas Gas 250 Size B

Wossner 8169DB Premium Forged 2-Stroke Piston Kit - Size B

Maintain the race-winning edge of your European 2-stroke with the Wossner 8169DB Piston Kit. Specifically engineered for KTM, Husqvarna, and Gas Gas 250cc cylinders that require a Size B fitment, this kit is the professional choice for restoring Factory Quality power and reliability. At Moto-House MX, we provide the high-performance forged components required to maintain peak compression in seasoned fuel-injected (TPI) and carbureted 250cc engines.

Forged from aerospace-grade aluminum alloy, this piston offers superior structural integrity and thermal resistance compared to standard cast alternatives. The permanent skirt coating is a critical feature, reducing internal friction and piston rock for a quieter engine and smoother throttle response. This Size B piston (66.35mm) is designed for cylinders with a 66.41mm bore, providing the precise clearances needed for optimal performance in cylinders that have seen standard use.

Top Features: Wossner 8169DB Piston Kit

• Standard Size B (66.35mm): Precision-engineered for 66.41mm bores to maintain perfect factory tolerances in used cylinders.
• Aerospace Forged Alloy: Premium aluminum construction for maximum durability and resistance to high-temperature fatigue.
• Low-Friction Skirt Coating: Permanent coating reduces wear and mechanical noise for a more efficient engine.
• Dual-Ring Design: Optimized for a consistent combustion seal and maximum compression across the powerband.
• Complete Assembly: Kit includes the forged piston, high-quality rings, wrist pin, and clips.

Expert Pro-Tip: Modern European 250cc cylinders are built with extremely high standards, but natural wear of the Nikasil plating occurs over time. Size B is the ideal selection for your second or third top-end refresh to compensate for this microscopic wear. When rebuilding TPI or carbureted models, always inspect your power valve for carbon buildup to ensure your powerband remains broad and predictable.

Fitment List

Brand	Models	Year Range
KTM	250 SX / XC / XC-W / EXC (Including TPI)	2005-2023
Husqvarna	TC250 / TE250 / TE250i	2014-2023
Gas Gas	MC 250 / EX 250 / EC 250	2021-2025
KTM	Freeride 250 R	2014-2018

Frequently Asked Questions

Q: What is the difference between Size A and Size B?
A: Size B (66.35mm) is exactly 0.01mm larger than Size A. This slight increase allows you to maintain the factory-specified piston-to-wall clearance as the cylinder wall experiences natural wear over time, preventing piston slap and maintaining compression.

Q: Does this kit work with TPI (Transfer Port Injection) models?
A: Yes, this forged piston is fully compatible with both carbureted and TPI fuel-injected 250cc engines from KTM, Husqvarna, and Gas Gas.

Q: Does this kit include the wrist pin bearing?
A: No, the kit includes the piston, rings, pin, and clips. We highly recommend purchasing a new small-end bearing separately whenever you perform a top-end refresh.

Recommended Pairings

• Top End Gasket Kit: Essential for a professional, leak-free engine rebuild.
• Motorex Cross Power 2T Oil: The recommended synthetic lubrication for high-performance European 2-strokes.

Restore your machine’s power and precision today. Buy now at Moto-House MX!

Moto-House MX – Choice of Champions – is located in Clermont/Montverde, FL. The Best Motocross/UTV & ATV Shop in Central Florida. Stop by our local store in Montverde, FL or enjoy lightning-fast shipping across the USA.