Wossner 8691D050 Piston Kit - Polaris Sportsman Scrambler Ranger 500 (+0.50mm)

Wossner 8691D050 Premium Forged 4-Stroke Piston Kit - +0.50mm Oversize

Restore the power and reliability of your Polaris 500cc engine with the Wossner 8691D050 Piston Kit. This +0.50mm oversize kit is specifically designed for Polaris Sportsman, Scrambler, and Ranger 500 models spanning nearly two decades of production. At Moto-House MX, we provide the precision-forged components needed to breathe new life into worn cylinders, ensuring your ATV or UTV remains a workhorse on the trail or the job site.

Forged from aerospace-grade aluminum alloy, this piston offers superior strength and thermal stability compared to standard cast replacements. The 8691D050 features advanced radial boss machining and enhanced oiling slots for improved wrist pin lubrication, which is vital for engine longevity in high-load utility environments. With a 10.3:1 compression ratio and a permanent skirt coating to reduce friction, this kit delivers a quieter-running engine and a more efficient break-in period.

Top Features: Wossner 8691D050 Piston Kit

• Oversize +0.50mm (92.45mm Piston): Precision-engineered for 92.50mm bores, perfect for cleaning up worn or damaged cylinder walls.
• Aerospace Forged Alloy: Provides maximum structural integrity to handle the mechanical stress of heavy-duty utility and off-road use.
• Advanced Lubrication Design: Radial boss machining and annular grooves ensure consistent oil delivery to the wrist pin for reduced wear.
• Low-Friction Skirt Coating: Permanent coating minimizes internal drag and piston rock for smoother, quieter operation.
• Improved Ring Seal: Specialized ring land treatment enhances oil control and maintains peak combustion efficiency.
• Complete Assembly: Kit includes the forged piston, high-performance rings, wrist pin, and pin locks.

Expert Pro-Tip: The Polaris 500 engine is a legend for its longevity, but after years of service, cylinder bores can become oval or scratched. This +0.50mm kit is the professional solution for an engine rebuild that requires boring. Always have your cylinder bored and honed by a qualified machinist to match this specific 92.45mm piston size for the correct piston-to-wall clearance.

Fitment List (Partial)

Model Group	Year Range	Vehicle Type
Polaris Sportsman 500 / HO / EFI	1996-2013	ATV
Polaris Scrambler 500 4x4 / 2x4	1997-2012	ATV
Polaris Ranger 500 / EFI / 4x4 / 6x6	2004-2013	UTV
Polaris Magnum / ATP / Xplorer 500	1997-2005	ATV

Frequently Asked Questions

Q: Is this a Standard Size piston?
A: No, this is an Oversize (+0.50mm) piston. Your cylinder must be bored and honed to 92.50mm to accommodate this kit.

Q: Does this kit include a gasket set?
A: No, the kit includes the forged piston, rings, wrist pin, and pin locks. A complete engine gasket set is required for a professional rebuild and is sold separately.

Q: Why choose forged over cast for a utility ATV?
A: Forged pistons are denser and stronger, making them much more resistant to cracking under the heavy thermal loads often seen in utility work or technical trail riding.

Recommended Pairings

• Complete Top End Gasket Set: Required for a leak-free reassembly.
• High-Performance 4-Stroke Engine Oil: Keep your new forged piston protected with premium lubrication.

Restore your Polaris to its prime. 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.