Wiseco WK1329 Yamaha Forged Piston Kit Bore - 1100 81.00mm 3189KD

The Wiseco WK1329 is a complete forged piston kit designed for Yamaha 1100cc 2-stroke personal watercraft engines. Built to an 81.00mm bore diameter (part number 791M08100), this kit delivers the precision fit and durability required for both high-performance and recreational riding. The kit includes the piston, ring set, wrist pin, and circlips — everything needed for a proper top-end rebuild.

Key Features:

• Forged High-Silicon Aluminum Construction: Each piston is forged from high-silicon, low-expansion aluminum alloy, providing superior strength, reduced reciprocating weight, improved heat transfer, and extended service life compared to OEM cast pistons.
• CNC Diamond-Turned Finish: Precision-machined on CNC turning centers to exact tolerances, ensuring a perfect bore fit with zero size variation across every unit produced.
• Universal Cylinder Compatibility: Engineered to install confidently in cast iron, chrome, Nikasil, and boron composite cylinder bore compositions without modification.
• Oversize Availability: The WK series is available in multiple oversize options to restore worn cylinders, compatible with resleevable chrome, Nikasil, and boron composite bores.
• Complete Kit Included: Kit part number 3189KD includes the piston, matched ring set, wrist pin, and circlips — all precision-matched components for a straightforward installation.
• USA Engineered and Manufactured: Designed and produced at Wiseco's state-of-the-art facility in Mentor, Ohio, applying over 80 years of forged piston expertise.

Cross-reference part number: 791M08100. Wiseco's WK1329 piston kit is the trusted choice for rebuilding Yamaha 1100 2-stroke PWC engines to factory specifications or performance levels.