Wiseco PK1743 4-Stroke Forged Piston Top-End Kit 101mm +1.00mm Oversize 8.7:1 CR

The Wiseco PK1743 is a complete 4-stroke forged piston top-end kit designed as a +1.00mm oversize rebuild solution, bringing the bore to 101.00mm with an actual compression ratio of 8.7:1. Built for the Honda XR650L and XR650R, this kit delivers the strength and precision that demanding off-road and dual-sport riding requires. Note: cylinder boring is required prior to installation.

Key Specifications:

• Bore (Actual): 101.00mm (+1.00mm oversize)
• Bore (Standard): 100.00mm
• Stroke: 82.00mm
• Displacement: 657cc
• Compression Ratio: 8.7:1
• Piston Part Number: 4562M10100

Kit Includes:

• Forged piston (#4562M10100)
• Piston ring set (#3977XH)
• Wrist pin (#S627)
• Circlip (#CW24)
• Top-end gasket (#W6231)

Why Wiseco Forged Pistons?

• Engineered, forged, and machined in the USA in Mentor, OH
• Designed specifically for each 4-stroke powersports engine application
• Built to the tightest tolerances for performance and durability
• Dedicated forgings deliver an optimized strength-to-weight ratio
• Superior tensile strength compared to cast pistons — resistant to impact and fatigue
• In-house dyno testing drives continuous R&D in piston shapes, coatings, and components

Unlike cast pistons, Wiseco forgings feature a condensed grain structure aligned to the geometry of the part, producing higher mechanical properties and dramatically better resistance to the catastrophic failures that can occur under high-performance motorsport conditions. This top-end kit provides everything needed for a proper engine rebuild in a single purchase.