The Athena S4C05400016A Cast Flat-Top Piston Kit is designed for select Yamaha YZ125 two-stroke motorcycles from 1997 through 2004. This standard-size piston kit features a 53.94 mm piston diameter and a 14.8:1 compression ratio, providing a reliable replacement for worn or damaged original components while supporting proper engine performance.
Manufactured by Athena, this cast piston kit is developed for dependable service in motocross and off-road applications. Its flat-top design is intended to match the original engine configuration and help maintain correct combustion-chamber compatibility. The kit is suitable for standard-bore applications and should be installed after confirming cylinder condition, piston clearance, and the manufacturer’s service specifications.
Fitment includes the 1997, 1998, 1999, 2000, 2001, 2002, 2003, and 2004 Yamaha YZ125. Verify the motorcycle year, engine configuration, and required piston size before installation. The manufacturer part number is Athena S4C05400016A, and the vendor part number is 68-4862A.
Features:
- Brand: Athena
- Manufacturer Part Number: S4C05400016A
- Vendor Part Number: 68-4862A
- Product Type: Cast flat-top piston kit
- Piston Size: 53.94 mm standard bore
- Compression Ratio: 14.8:1
- Fitment: 1997–2004 Yamaha YZ125
- Application: Replacement piston for Yamaha YZ125 two-stroke engines
Fitment:
1997 Yamaha YZ125
1998 Yamaha YZ125
1999 Yamaha YZ125
2000 Yamaha YZ125
2001 Yamaha YZ125
2002 Yamaha YZ125
2003 Yamaha YZ125
2004 Yamaha YZ125