Namura NX-10027K Top End Kit for 2002–2004 Honda CR250R, 66.34 mm Standard Bore, 8.5:1 Compression

The Namura NX-10027K Top End Kit is designed for 2002, 2003, and 2004 Honda CR250R models equipped with a Nikasil cylinder. This complete standard-bore kit includes a piston, piston rings, wrist pin, circlips, top-end bearing, and gasket kit for a convenient engine rebuild. It is manufactured to support reliable fitment and performance for compatible Honda CR250R applications.

The piston uses Namura’s hypereutectic casting process to provide increased silicon content, reduced expansion, enhanced wear resistance, and improved durability under elevated cylinder temperatures. The 66.34 mm standard-bore piston features an 8.5:1 compression ratio and is engineered for use with the original cylinder specification when service conditions are appropriate.

Additional piston features are designed to promote dependable operation. The MOS2, or Teflon/molybdenum, coated skirts help reduce friction, improve heat transfer, and minimize the risk of cold seizures. Machined-smooth heads help reflect combustion heat and reduce carbon buildup, while anodized domes improve heat resistance and piston durability. The included components provide the essential parts needed for a complete top-end service.

Fitment: 2002 Honda CR250R, 2003 Honda CR250R, and 2004 Honda CR250R. Verify cylinder condition, bore specification, compression ratio, and application details before installation. Manufacturer part number: NX-10027K. Vendor part number: 185-1027. Brand: Namura.

Features:

• Complete top-end kit includes piston, rings, wrist pin, circlips, top-end bearing, and gasket kit
• Fits 2002–2004 Honda CR250R models with a compatible Nikasil cylinder
• 66.34 mm standard-bore piston with an 8.5:1 compression ratio
• MOS2 Teflon/molybdenum-coated skirts help reduce friction, improve heat transfer, and minimize cold-seizure risk
• Machined-smooth piston head helps reflect combustion heat and reduce carbon buildup
• Anodized dome improves heat resistance and piston durability
• Hypereutectic casting process provides reduced expansion, increased wear resistance, and improved high-temperature performance
• Brand: Namura
• Manufacturer part number: NX-10027K
• Vendor part number: 185-1027