Wossner 8941DB Piston Kit - 2017-2019 KTM 350 EXC-F Husqvarna FE350 Size B

Wossner 8941DB Pro Series Forged 4-Stroke Piston Kit - Standard Size B

Refresh the heart of your dual-sport machine with the Wossner 8941DB Piston Kit. Specifically designed for the 2017-2019 KTM 350 EXC-F and Husqvarna FE350, this "Size B" forged kit is the professional choice for riders performing a mid-life top-end service. At Moto-House MX, we know that the 350cc platform is the perfect balance of agility and power; Wossner’s Pro Series forging ensures your bike maintains that legendary performance while offering superior durability over standard cast alternatives.

The 8941DB is engineered to handle the rigorous demands of both technical trails and street transitions. It features a high-strength double-bridged forging design that provides structural stability at high RPMs without adding unnecessary weight. To maximize engine longevity, Wossner has included enhanced piston pin oiling slots and radial boss machining for improved wrist pin lubrication. The piston skirt is treated with a permanent coating to reduce internal friction and ensure a quiet, efficient engine. Precision-machined for 88.01mm bores, this 87.96mm Size B kit restores your 350 to its peak operating efficiency.

Top Features: Wossner 8941DB Piston Kit

• Standard Size B (87.96mm): Precision-engineered for 88.01mm bores to account for minor cylinder wear and restore factory-correct mechanical clearances.
• Pro Series Forging: Advanced double-bridged design offers exceptional strength-to-weight ratios, ideal for high-revving 4-stroke engines.
• Superior Lubrication: Integrated radial boss machining and oiling slots ensure the wrist pin stays lubricated during extended dual-sport rides.
• Low-Friction Skirt Coating: Permanent skirt treatment minimizes drag, protects the cylinder walls, and provides a smoother break-in period.
• Reliable 12.5:1 Compression: Maintains factory-spec compression for a smooth, predictable powerband that works perfectly with pump gas.
• Complete Kit: Includes the high-performance forged Size B piston, rings, wrist pin, and pin locks.

Expert Pro-Tip: The KTM and Husqvarna 350cc dual-sport engines are built to high standards, but performance eventually drops as clearances widen. If you are servicing a cylinder with moderate hours, the Size B (87.96mm) is the expert recommendation to bring your piston-to-wall gap back into the ideal range. Always use a precision bore gauge to confirm your cylinder measures 88.01mm before installation. For a professional-grade rebuild, always install with a fresh top-end gasket kit and premium synthetic oil to protect your forged assembly.

Fitment List

Year Range	Vehicle Brand	Vehicle Model
2017-2019	KTM	350 EXC-F
2017-2019	Husqvarna	FE350

Frequently Asked Questions

Q: When should I use Size B instead of Size A?
A: Size B (87.96mm) is 0.01mm larger than Size A. It is used to maintain a tight seal in a cylinder that has experienced a small amount of natural wear, ensuring you don't lose compression or experience piston slap.

Q: Is this piston compatible with the factory ECU mapping?
A: Yes, with a 12.5:1 compression ratio, this piston is designed to work seamlessly with the original engine parameters and high-quality pump gas.

Q: What are the benefits of a forged piston for dual-sport riding?
A: Forged pistons are much more resistant to heat and mechanical fatigue than cast pistons. This is vital for dual-sport bikes that may see high temperatures during slow, technical trail sections or sustained RPMs on the road.

Recommended Pairings

• Complete Top End Gasket Set: Vital for ensuring a leak-free rebuild and maintaining the correct squish gap.
• High-Performance Oil Filter: Protect your new forged assembly by ensuring the cleanest possible oil flow from the first start-up.

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

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