The NAMURA NA-40007K Top End Kit is a complete 95 mm standard-bore engine rebuild solution designed for select Yamaha XT600 models from 1984 through 1993. Built for dependable fitment and performance, this 11:1 compression kit includes a piston, piston rings, wrist pin, wrist-pin clips, top-end bearing, and gasket kit. It is intended for restoring the top end of compatible Yamaha XT600 engines while providing the components needed for a thorough installation.
The piston uses NAMURA’s MOS2, or Teflon/molybdenum, coated skirts. This rolled-on coating process creates a durable bond that helps improve heat transfer, reduce friction, and minimize the risk of cold seizures. Machined smooth heads help reflect combustion heat and reduce carbon buildup, supporting piston protection and consistent engine operation. The anodized dome improves heat resistance and durability, while the hypereutectic casting process adds silicon for reduced expansion, increased wear resistance, and improved performance under higher cylinder temperatures.
Fitment includes 1984–1993 Yamaha XT600 motorcycles, provided the engine matches the standard-bore application and required specifications. Verify the model year, bore size, compression ratio, and engine configuration before installation. The NAMURA brand and manufacturer part number NA-40007K provide reliable reference points when selecting a replacement top-end assembly for your Yamaha XT600.
Features:
- Complete top-end kit includes piston, rings, wrist pin, clips, top-end bearing, and gasket kit
- 95 mm standard-bore piston with an 11:1 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
- Fits 1984–1993 Yamaha XT600 models when matched to the standard-bore engine configuration
Fitment:
1984 Yamaha XT600
1985 Yamaha XT600
1986 Yamaha XT600
1987 Yamaha XT600
1988 Yamaha XT600
1989 Yamaha XT600
1990 Yamaha XT600
1991 Yamaha XT600
1992 Yamaha XT600
1993 Yamaha XT600
1994 Yamaha XT600
1995 Yamaha XT600
1998 Yamaha YFM600FG Grizzly 4WD [SRA]
1999 Yamaha YFM600FG Grizzly 4WD [SRA]
2000 Yamaha YFM600FG Grizzly 4WD [SRA]
2001 Yamaha YFM600FG Grizzly 4WD [SRA]