Wiseco PK1203 Pro-Lite 2-Stroke Piston Kit 48.0mm for Yamaha YZ85

The Wiseco PK1203 Pro-Lite Piston Kit is a complete top-end rebuild solution for the Yamaha YZ85, featuring a forged 48.0mm (805M) bore piston engineered for all-purpose two-stroke performance. Wiseco's Pro-Lite series is the forged 2-stroke piston that started it all, combining decades of manufacturing experience with race-proven design for reliable power delivery.

Kit Includes:

• 1 Pro-Lite forged piston (48.0mm / 805M bore)
• Ring set (Wiseco-specific — not interchangeable with other brands)
• Wrist pin
• Circlips
• Top-end wrist pin bearing
• Complete top-end gasket kit

Key Features:

• Forged aerospace alloy construction — superior strength-to-weight ratio for responsive power delivery
• Lightweight design — extra lightweight forging for instant throttle response and maximum torque
• Computer-engineered piston skirt profile — minimizes cylinder wall friction for reduced wear and improved efficiency
• Anti-detonation grooves — ring land diameter eliminates ring blow-by while maximizing performance
• High-silicon bar stock forging — greater strength and lower thermal expansion at high operating temperatures
• Race-proven design — chosen by top race teams in Supercross, Motocross, and GNCC competition

The PK1203 is an overbore kit at 48.0mm, making it ideal for top-end rebuilds when the cylinder has been bored beyond the standard 47.5mm dimension. Note: Wiseco rings are not interchangeable with other ring types (such as CD or LC) — always use Wiseco rings with Wiseco pistons.