Wiseco 393M06450 Forged Piston Kit Oversize Bore - 0.50mm 64.50mm 2-Stroke

The Wiseco 393M06450 is a classic forged piston kit designed as a 0.50mm oversize replacement, bringing the bore diameter to 64.50mm for Yamaha RD350 and RD400 two-stroke engines. Each kit includes the piston, rings, wrist pin, and circlips — everything needed for a complete single-cylinder rebuild.

Key Features:

• Forged from high-silicon, low-expansion aluminum alloy for superior strength, reduced weight, improved heat transfer, and extended service life
• Diamond-turned finish produced on CNC-controlled turning centers for a precise, consistent bore size with no variation
• Optimized strength-to-weight ratio through dedicated forgings and precision lightening operations
• Compatible with all common cylinder bore compositions including cast iron, chrome, Nikasil, and boron composite
• Engineered, forged, and machined in the USA at Wiseco's facility in Mentor, OH
• Kit includes: piston, ring(s), wrist pin, and circlips
• Oversize pistons require cylinder resleeving or reboring — compatible with replacement cylinder sleeves for chrome, Nikasil, and boron composite cylinders
• Wiseco rings are piston-specific; rings from different Wiseco series (e.g., CD vs. LC) are not interchangeable

Part of Wiseco's Classic Forged piston line, the 393M06450 is built on over 80 years of two-stroke piston engineering expertise. This kit is ideal for restorers and performance builders looking to bring a worn RD-series engine back to spec or push it beyond stock displacement limits.