Athena Piston Kit for Yamaha YZ125 (S4F05400017C)

Upgrade the performance and durability of your Yamaha YZ125 with the ATHENA S4F05400017C Piston Kit. Designed for demanding two-stroke applications, this piston kit is engineered to withstand high mechanical and thermal stresses while supporting consistent performance during intense riding and racing conditions. Its construction has been tested on engine dynamometer benches under progressive stress loads and subsequently validated on the track to confirm reliable operation in extreme environments.
The ATHENA S4F05400017C is manufactured using a reverse extrusion process that supports strength, precision, and dependable fitment in the original equipment cylinder. The included piston rings are designed to reduce friction against the OE cylinder, helping improve power delivery, engine efficiency, and overall operating performance. This kit is intended for Yamaha YZ125 applications requiring a 53.97 mm piston size.
Built for riders and technicians who demand dependable replacement components, the ATHENA piston kit combines tested materials, precise manufacturing, and application-specific design. It is a practical choice for restoring engine performance during a rebuild or replacing worn piston components while retaining compatibility with the original cylinder. Always verify model-year fitment and service specifications before installation.

Features:

• High resistance to mechanical and thermal stresses

• Tested on engine dynamometer benches under progressive stress loads

• Track-tested for performance in extreme riding conditions

• Piston rings designed to reduce friction against the OE cylinder

• Supports improved engine performance and power delivery

• Manufactured using a reverse extrusion process

• Designed for use with the OE cylinder

• 53.97 mm piston size for Yamaha YZ125 applications

Ships from Parts Unlimited.