The NAMURA NA-10002-4K Top End Kit is a complete 74.95 mm (+1.00 mm) replacement kit designed for Honda TRX300 FourTrax models from 1988 through 1997. With an 11:1 compression ratio, this kit provides the essential components needed for a reliable top-end rebuild, including the piston, piston rings, wrist pin, retaining clips, top-end bearing, and gasket kit.
The hypereutectic piston casting process increases silicon content to help control thermal expansion while improving wear resistance and durability under elevated cylinder temperatures. The piston features a machined smooth head that reflects combustion heat and helps reduce carbon buildup, supporting consistent performance and protecting the piston crown. Its anodized dome improves heat resistance and provides greater strength compared with non-anodized piston domes.
The piston skirts use NAMURA's MOS2, or Teflon/molybdenum, coating. This rolled-on coating process creates a strong bond while reducing friction, improving heat transfer, and helping minimize the risk of cold seizures during operation. The included components and gaskets support a convenient, application-specific installation for the listed Honda ATV models. Verify the cylinder condition, required oversize, compression ratio, and year-specific specifications before installation.
Fitment includes 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, and 1997 Honda TRX300 FourTrax models. NAMURA is the brand and manufacturer associated with part number NA-10002-4K; the vendor part number is 186-10024.
Features:
- Complete top-end kit includes piston, rings, wrist pin, retaining clips, top-end bearing, and gasket kit.
- 74.95 mm (+1.00 mm) piston size with an 11:1 compression ratio for compatible Honda TRX300 FourTrax applications.
- MOS2 Teflon/molybdenum-coated piston skirts help reduce friction, improve heat transfer, and minimize cold-seizure risk.
- Machined smooth piston head reflects combustion heat and helps reduce carbon buildup.
- Anodized piston dome improves heat resistance, durability, and crown strength.
- Hypereutectic casting process provides controlled expansion, increased wear resistance, and improved high-temperature performance.
- Fitment: 1988-1997 Honda TRX300 FourTrax.
- Brand and manufacturer: NAMURA; part number: NA-10002-4K; vendor part number: 186-10024.
Fitment:
1988 Honda TRX300 Fourtrax
1988 Honda TRX300FW Fourtrax 4X4
1989 Honda TRX300 Fourtrax
1990 Honda TRX300 Fourtrax
1990 Honda TRX300FW Fourtrax 4X4
1991 Honda TRX300 Fourtrax
1991 Honda TRX300FW Fourtrax 4X4
1992 Honda TRX300 Fourtrax
1992 Honda TRX300FW Fourtrax 4X4
1993 Honda TRX300 Fourtrax
1993 Honda TRX300FW Fourtrax 4X4
1994 Honda TRX300 Fourtrax
1994 Honda TRX300FW Fourtrax 4X4
1995 Honda TRX300 Fourtrax
1995 Honda TRX300FW Fourtrax 4X4
1996 Honda TRX300 Fourtrax
1996 Honda TRX300FW Fourtrax 4X4
1997 Honda TRX300 Fourtrax
1997 Honda TRX300FW Fourtrax 4X4
1998 Honda TRX300 Fourtrax
1998 Honda TRX300FW Fourtrax 4X4
1999 Honda TRX300 Fourtrax
1999 Honda TRX300FW Fourtrax 4X4
2000 Honda TRX300 Fourtrax
2000 Honda TRX300FW Fourtrax 4X4