Namura .020 Over Bore Piston Kit for Yamaha BearTracker 250 1999-2004 71.5mm

.020 Over Bore Piston Kit for Yamaha BearTracker 250 1999-2004 71.5mm

This .020 over bore piston kit for Yamaha BearTracker 250 models from 1999 to 2004 provides a 71.5mm piston assembly designed to restore compression and power in worn engines. It includes rings, wrist pin, and circlips, offering a direct replacement for engines requiring a .020 oversize bore.

Overview

This .020 over bore piston kit for Yamaha BearTracker 250 replaces the original piston with a 71.5mm oversized unit, allowing the cylinder to be rebored to remove scoring or wear. It is intended for owners restoring top-end performance on 1999-2004 BearTracker 250 ATVs, delivering reliable operation and extended engine life.

Built For Performance

• Precision-machined 71.5mm piston for .020 over bore applications
• Includes high-strength rings, wrist pin, and circlips for a complete top-end rebuild
• Cast from durable aluminum alloy for consistent thermal expansion
• Designed to match OEM specifications for fit and clearance
• Tested for reliable sealing and reduced blow-by

Fits These Machines

• for Yamaha BearTracker 250 (1999-2004)

On-The-Job Use

• Rebuilding top-end after cylinder scoring or ring failure
• Restoring compression on high-mileage BearTracker 250 engines
• Performing a scheduled engine overhaul for trail or utility ATVs

Specs At A Glance

Good To Know

Q: Will this kit work with the stock cylinder? A: The cylinder must be bored to 71.5mm by a qualified shop to match this piston; the kit itself does not include a cylinder.

Q: Is the piston pre-gapped for rings? A: Ring end gap should be checked and adjusted per service manual specs during installation.

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