Wiseco PK1349 Pro-Lite 54.5mm Piston Kit 2001 Yamaha YZ125

The Wiseco PK1349 is a Pro-Lite forged piston kit designed for the 2001 Yamaha YZ125, featuring a 54.5mm bore diameter (726M oversize). Wiseco's Pro-Lite pistons are CNC-machined from aerospace-grade forged aluminum alloy, offering superior strength, reduced weight, and improved heat dissipation compared to cast alternatives — making them a popular choice for motocross and off-road racing applications.

Kit Contents:

• 1x Forged Pro-Lite piston (54.5mm / 726M)
• Piston ring set
• Wrist pin (piston pin)
• Circlip retainers

Key Features:

• Forged aluminum construction — stronger and lighter than OEM cast pistons
• 54.5mm bore diameter — designed for standard oversize rebuild or overbore applications
• Pro-Lite design — reduced reciprocating mass for improved throttle response and high-RPM performance
• Precision CNC machined — tight tolerances for optimal ring seal and long service life
• Direct OEM replacement geometry — retains stock compression ratio and port timing

Designed as a complete top-end piston assembly for the 2001 Yamaha YZ125, the PK1349 simplifies the rebuild process by including all essential piston assembly components. Compatible with the 726M cylinder bore specification. A top-end gasket set is recommended for a full rebuild and is sold separately.