Namura Technologies NA-10003-6K Top End Repair Kit 86.50mm High Compression 11:1

The Namura Technologies NA-10003-6K is a complete top end repair kit engineered for high-compression 11:1 applications with an 86.50mm bore. Designed as a direct OEM replacement, this kit provides everything needed to restore engine performance in a single package — no additional sourcing required.

What's Included:

• High-compression piston (86.50mm bore, 11:1 compression ratio)
• OEM-quality piston rings
• Wrist pin and circlips
• Top end needle bearing
• Complete top end gasket set (head gasket, base gasket, O-rings, and valve guide seals as applicable)

Piston Features:

• MOS2 (Molybdenum/Teflon) Coated Skirts — Applied via a rolled-on process that bonds 10 times stronger than conventional spray-on coatings, reducing friction, improving heat transfer, and helping prevent cold seizures
• Machined Smooth Crown — Reflects combustion heat, reduces carbon buildup, and protects the top of the piston; testing has shown potential gains of up to 6% in horsepower and fuel economy
• Anodized Dome — Increases heat resistance and structural durability; anodized pistons are up to 75% stronger than non-anodized equivalents
• Hypereutectic Aluminum Casting — Higher silicon content lowers thermal expansion rates, adds wear resistance, and allows the piston to withstand elevated cylinder temperatures

OEM-Quality Rings by Riken — Namura rings are manufactured by Riken, the world's largest OEM ring manufacturer, ensuring precise fitment and reliable sealing. A, B, and C grade pistons are available to help extend the life of Nikasil, SCEM, Boron Composite, and Ceramic-lined cylinders.

The NA-10003-6K top end kit is a trusted solution for powersports engine rebuilds, delivering performance and longevity that meets or exceeds original equipment standards.