Wiseco PK1201 Pro-Lite 2-Stroke Piston Kit 68.5mm Bore YZ250

The Wiseco PK1201 is a complete Pro-Lite forged 2-stroke piston kit with a 68.50mm actual bore (2.10mm oversize), designed for the Yamaha YZ250. This kit delivers the durability and performance that serious dirt bike riders demand, combining aerospace-grade forged construction with precision CNC machining — all engineered and manufactured in the USA.

Kit Specifications:

• Actual Bore: 68.50mm
• Standard Bore: 66.4mm
• Oversize: +2.10mm
• Stroke: 72.00mm
• Displacement: 265cc
• Cylinders: 1
• Note: Pro-Lite design; ceramic composite bore — cylinder sleeving or replating required

Kit Includes:

• 1 forged piston
• 1 high-performance ring set
• 1 alloy wrist pin
• 2 circlips
• Top-end bearings
• Top-end gasket kit

Key Features:

• Forged aerospace alloy construction — engineered, forged, and machined in the USA in Mentor, OH
• Dedicated forging designed specifically for this 2-stroke powersports engine for optimal fit and performance
• Optimized strength-to-weight ratio — dedicated forgings with additional lightening operations reduce reciprocating mass for faster throttle response
• Improved tensile strength — forged material structure resists impact and fatigue far better than cast alternatives
• CNC-machined cam profile optimized for peak horsepower and extended service life
• High-performance ring set for sustained power delivery and extended service intervals
• Race-proven design — chosen by top race teams across all forms of racing

Wiseco's Pro-Lite series is the forged 2-stroke piston that started it all, drawing on over 80 years of piston manufacturing experience. Whether you're rebuilding for weekend trail riding or competitive motocross, the PK1201 provides the precision and reliability needed to get the most out of your YZ250's top end.