Namura .040 Over Bore Piston Kit for Polaris Sportsman 550 fits 2009-2014 97.6mm

Namura .040 Over Bore Piston Kit for Polaris

This .040 over bore piston kit from Namura replaces the original pistons in Polaris Sportsman 550 engines manufactured between 2009 and 2014, utilizing a 97.6mm bore diameter for oversize rebuilds.

Overview

The Namura .040 over bore piston kit is a direct-fit replacement for Polaris Sportsman 550 ATVs from 2009 to 2014. This .040 over bore kit features a 97.6mm bore size and includes rings, wrist pin, and clips for a complete top-end rebuild. It restores lost compression and power in high-mileage engines, making it an ideal choice for riders performing an overbore service.

Built For Performance

• Precision-machined from high-silicon aluminum alloy for durability
• Includes moly-coated rings for reduced friction and improved sealing
• 97.6mm bore diameter provides a .040 over size for cylinder oversize repair
• Includes wrist pin and circlips for complete installation
• Designed to match Polaris Sportsman 550 OEM specifications

Fits These Machines

• for Polaris Sportsman 550 (2009-2014)

On-The-Job Use

• Rebuilding top-end of Polaris Sportsman 550 engines after wear
• Restoring compression and power in high-mileage ATVs
• Performing an overbore service to renew cylinder walls
• Replacing damaged or worn pistons during engine overhaul

Specs At A Glance

Good To Know

Q: Does this piston kit include a gasket set? A: This kit includes the piston, rings, wrist pin, and circlips only. A separate gasket set is recommended for a complete rebuild.

Q: Can this kit be used with a standard bore cylinder? A: No, this is a .040 over bore piston, so the cylinder must be bored to 97.6mm by a machine shop before installation.

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