Namura Technologies NA-50025-4K Top End Repair Kit Polaris +1mm Overbore

The Namura Technologies NA-50025-4K is a complete top end rebuild kit designed for Polaris powersports engines, featuring a +1mm overbore piston for worn cylinders. This comprehensive kit includes everything needed for a professional-quality top end rebuild: piston, rings, wrist pin, circlips, top end bearing, and complete gasket set.

Advanced Piston Features:

• MOS2 Coated Skirts: Teflon/Molybdenum coating applied through a rolled-on process creates a bond 10 times stronger than spray-on alternatives, increasing heat transfer, reducing friction, and preventing cold seizures
• Machined Smooth Crown: Precision-machined piston head reflects combustion heat and minimizes carbon buildup while potentially increasing horsepower and fuel economy by up to 6%
• Anodized Dome: Hard anodized treatment increases heat resistance and durability, making the piston crown 75% stronger than non-anodized pistons
• Hypereutectic Construction: High-silicon casting process delivers reduced thermal expansion, superior wear resistance, and improved ability to withstand extreme cylinder temperatures

This +1mm overbore kit is ideal for restoring compression and performance in worn engines or as part of a complete engine rebuild. All Namura pistons are engineered to meet or exceed OEM specifications for reliable performance and long service life.