Namura .040 Over Bore Piston Bearing Gasket Kit for Yamaha YZ85 2002-2018 48.5mm

Namura .040 Over Bore Piston Bearing Gasket Kit for Yamaha

This piston and gasket kit replaces the original top end components for Yamaha YZ85 motorcycles from 2002 to 2018, delivering reliable power and a precise fit with its .040 over bore size of 48.5mm.

Overview

This Namura .040 over bore piston bearing and gasket kit is designed for Yamaha YZ85 models from 2002 to 2018, providing a complete top-end rebuild solution. It includes a forged piston, rings, pin, bearings, and all necessary gaskets to restore compression and performance. The 48.5mm bore size matches the .040 oversize specification for a snug fit in a refurbished cylinder.

Built For Performance

• Forged aluminum piston for high-strength and durability
• Precision-machined wrist pin and bearing reduce friction
• Complete gasket set seals combustion chamber effectively
• .040 over bore compensates for cylinder wear and extends engine life
• Includes rings pre-gapped for quick installation

Fits These Machines

• for Yamaha YZ85 (2002-2018)

On-The-Job Use

• Ideal for rebuilding the top end of Yamaha YZ85 engines after wear or damage
• Suitable for motocross racing and trail riding applications
• Commonly used during engine overhauls to restore performance
• Installed when upgrading to an overbore size for increased displacement

Specs At A Glance

Good To Know

Q: Is this kit compatible with other Yamaha models? A: This kit is specifically designed for the Yamaha YZ85 from 2002 to 2018; other models may require different piston sizes or configurations.

Q: Do I need to re-bore the cylinder for this piston? A: Yes, the .040 over bore piston requires the cylinder to be bored to 48.5mm to ensure proper clearance and ring seal.

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