Wiseco PK1303 Pro-Lite Top End Piston Kit for Kawasaki - 2-Stroke 50.00mm KX80 1991-1997

The Wiseco PK1303 is a Pro-Lite forged 2-stroke top end piston kit designed for the 1991–1997 Kawasaki KX80. Featuring a 50.00mm bore (2.00mm oversize) with forging code 644M05000, this kit delivers the strength, durability, and precision that competitive dirt bike riding demands.

Kit Includes:

• Pro-Lite forged piston (50.00mm / 644M05000)
• High-performance piston ring set (1969CD)
• Alloy wrist pin (14mm x 1.510 in.)
• Round wire pin locks / circlips (14mm pair)
• Top-end needle bearing (14 x 18 x 17.2mm)
• Complete top-end gasket kit for Kawasaki KX80 1991–1997

Key Features:

• Forged aerospace alloy construction — high-silicon, low-expansion aluminum provides superior strength, reduced weight, improved heat transfer, and longer service life compared to cast pistons
• CNC machined for optimal cam shape and piston profile, delivering peak power and consistent long-term performance
• Horizontal slot-pin oiling reduces friction and improves scuff resistance; pressure seal groove maximizes ring seal
• Anti-detonation grooves and precision ring land diameter eliminate ring blow-by
• Race-ready dome design with smooth edges for improved combustion flow and throttle response
• Dedicated forgings optimized for the KX80 engine — not a one-size-fits-all casting
• Compatible with cast iron, chrome, Nikasil, and boron composite cylinder bore compositions
• Engineered, forged, and machined in the USA

Specifications:

• Bore Size: 50.00mm
• Oversize: 2.00mm over standard
• Forging Number: 644M05000
• Ring Set: 1969CD
• Wrist Pin: 14mm
• MPN: PK1303

Note: This is an oversize piston kit. Cylinder sleeving or re-plating/re-Nikasil is required for proper fitment. Wiseco piston rings are not interchangeable with other brands and must be used exclusively with Wiseco pistons.

The Wiseco Pro-Lite is the forged 2-stroke piston trusted by top race teams across Supercross, Motocross, and GNCC. Whether you're rebuilding a worn top end or increasing displacement, PK1303 gives you everything needed to complete a full rebuild in one purchase.