Wossner 8097D100 Piston Kit - Polaris Scrambler Sportsman Xplorer 400 +1.00mm Oversize

Wossner 8097D100 Standard Series Forged 2-Stroke Piston Kit - +1.00mm Oversize

Restore the legendary power of your Polaris 400cc liquid-cooled engine with the Wossner 8097D100 Piston Kit. Specifically engineered for the high-performance Polaris 2-stroke engine found in the Scrambler, Sportsman, and Xplorer 400 series, this +1.00mm oversize forged kit is the professional choice for cylinders that require boring to clear up heavy scoring or wear. At Moto-House MX, we know these 400cc engines are known for their impressive torque; upgrading to a Wossner forged piston provides superior structural integrity and heat resistance compared to original cast pistons, ensuring your machine stays reliable on the trail or the job site.

The 8097D100 features a robust dual-ring configuration, which is essential for maintaining a consistent compression seal and improving heat transfer in high-displacement 2-stroke engines. To ensure smooth operation and reduced engine noise, Wossner applies a permanent molybdenum disulphide skirt coating that minimizes friction and protects the cylinder wall from wear. Precision-machined for an 84.00mm finished bore, this 83.93mm piston kit is the ultimate solution for refreshing your high-hour Polaris 400 engine.

Top Features: Wossner 8097D100 Piston Kit

• +1.00mm Oversize (83.93mm): The ideal choice for cylinders requiring a precision bore to an 84.00mm finished size to restore a perfect mechanical seal.
• Dual Ring Configuration: Provides enhanced cooling and a reliable, long-term compression seal for the high-torque demands of a 400cc 2-stroke.
• Aerospace-Grade Forging: Crafted for significantly higher strength and durability than standard cast pistons, offering peace of mind during aggressive riding.
• Low-Friction Skirt Coating: Permanent skirt treatment reduces internal drag and piston rock, leading to a quieter engine and a safer break-in period.
• Optimized Machining: Engineered for lightness to improve throttle response while maintaining maximum strength in the crown and skirt walls.
• Complete Kit: Includes the high-performance forged +1.00mm piston, rings, wrist pin, and circlips.

Expert Pro-Tip: The Polaris 400 2-stroke is a powerhouse, but it generates significant heat. When moving to a +1.00mm oversize, it is critical that your cylinder is precision-bored and honed by a professional machine shop to exactly 84.00mm. This ensures the correct piston-to-wall clearance for a forged assembly. For a professional-grade rebuild, always install with a fresh top-end gasket kit and utilize premium 2-stroke oil to protect your new forged assembly from the very first start.

Fitment List

Year Range	Vehicle Brand	Vehicle Model
1995-2003	Polaris	Scrambler 400 / 4x4 / 2x4
1994-2003	Polaris	Sportsman 400 / 400L / 4x4
1995-2003	Polaris	Xplorer 400 / 400L / 4x4 / 4x2
1995-2003	Polaris	Xpress 400 / 400L / 4x4
1995-2003	Polaris	Big Boss 400L / Hawkeye 400 / Trail Blazer 400

Frequently Asked Questions

Q: Why should I choose a forged Wossner piston for my Polaris 400?
A: Forged pistons are much stronger than the factory cast pistons. In a high-displacement 2-stroke like the Polaris 400, forging provides the density and heat resistance needed to prevent cracks and withstand the stress of high-RPM operation.

Q: What is the advantage of the +1.00mm oversize?
A: It allows you to save a cylinder that has deep scratches or is worn beyond the limits of a smaller oversize. By boring to 84.00mm, you create a fresh, round surface for the new piston and rings to seal against.

Q: Does this kit include the wrist pin bearing?
A: This kit includes the forged piston, rings, wrist pin, and circlips. The needle bearing for the small end is sold separately. We always recommend replacing the bearing whenever a new piston is installed.

Recommended Pairings

• Complete Top End Gasket Set: Essential for maintaining proper compression and preventing coolant leaks.
• High-Performance 2-Stroke Premix Oil: Ensure your new oversize forged piston is lubricated and protected under heavy loads.

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.