Namura .040 Over Bore Piston Bearing & Gasket Kit for Yamaha 1993-2001 YZ80 48mm

Namura .040 Over Bore Piston Bearing & Gasket Kit for Yamaha

This Namura .040 over bore piston bearing and gasket kit replaces the original piston assembly for Yamaha YZ80 models from 1993 to 2001, providing a 48mm bore size for a refreshed top end rebuild. The kit includes a precision-machined piston, rings, wrist pin, bearings, and all necessary gaskets to restore compression and performance.

Overview

This Namura .040 over bore piston bearing and gasket kit is a complete top-end rebuild solution for Yamaha YZ80 motorcycles, designed to bring worn cylinders back to like-new condition. It includes every component needed for a direct swap, saving you time sourcing individual parts, and is built to match original specifications for reliable power delivery.

Built For Performance

• Precision-machined 48mm piston from high-silicone aluminum alloy for durability and heat resistance
• Includes premium chrome-plated piston rings for consistent compression and low friction
• Needle bearing wrist pin and cage assembly reduces friction and extends top-end life
• Complete gasket set contains all base, head, and exhaust gaskets for a leak-free seal

Fits These Machines

• for Yamaha YZ80 (1993-2001)

On-The-Job Use

• Ideal for motocross and off-road racing where top-end reliability is critical
• Commonly used during full engine rebuilds or when restoring a used YZ80 cylinder
• Suited for riders who need a direct replacement after a bore or cylinder refinish

Specs At A Glance

Good To Know

Q: Does this kit come with the wrist pin circlips? A: Yes, the kit includes the wrist pin, circlips, and needle bearing – everything you need for the piston installation.

Q: Will this .040 over piston work if my cylinder has already been bored? A: This piston is sized for a cylinder that has been bored to 48.00mm, so you must confirm your cylinder bore matches before ordering. If your cylinder is at standard bore or a different oversize, this kit will not fit.

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