797M05400 Wiseco Std Piston Kit for Yamaha YZ125 2002-2004 54.00 mm

Wiseco Std Piston Kit for Yamaha YZ125

This Wiseco Std piston kit (OEM cross-reference 797M05400) is a 54.00 mm standard bore piston assembly that brings compression and top end performance back to specification on Yamaha YZ125 engines.

Overview

This Wiseco Std piston kit for Yamaha YZ125 offers a standard bore replacement at 54.00 mm for engines that do not need machining. Riders and mechanics use it to refresh the top end and keep power delivery consistent. It is aimed at those who want a straightforward rebuild with a trusted piston design.

Built For Performance

• 54.00 mm standard bore piston that matches the original cylinder size
• Piston, rings, wrist pin and clips supplied as a complete top end kit
• Built from high silicon content alloy for heat resistance and durability
• Machined to maintain proper clearances for a two stroke engine
• OEM cross-reference 797M05400 for simple parts matching

Fits These Machines

• for Yamaha YZ125 2002
• for Yamaha YZ125 2003
• for Yamaha YZ125 2004

On-The-Job Use

• Standard bore top end refresh on a tired engine
• Rebuilds after compression loss or piston wear
• Routine maintenance intervals on a raced two stroke
• Trail and moto riding where reliable power matters

Specs At A Glance

Good To Know

Q: Will this kit fit a cylinder that has already been bored? A: This kit is made for a standard 54.00 mm bore, so it suits an unmodified cylinder. If the cylinder has been machined oversize, a different piston size is needed.

Q: Is everything needed for the rebuild included? A: The kit includes the piston, rings, wrist pin and clips for the top end. Gaskets and bearings are separate, so check the job before ordering.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.