Wiseco PK1442 Top End Piston Kit 78.5mm Standard Bore 8.8:1 Compression

The Wiseco PK1442 is a complete top end piston kit designed for the Honda TRX350 FourTrax Rancher (2000–2006). Built to a 78.50mm standard bore with an 8.8:1 compression ratio, this kit delivers everything needed for a full top end rebuild in a single package.

Wiseco forges all pistons in-house at their facility in Mentor, Ohio using aerospace-grade alloy. Unlike cast pistons, forged pistons feature a condensed grain structure aligned to the shape of the part, resulting in superior mechanical strength, impact resistance, and fatigue resistance. Each dedicated forging is engineered specifically for the TRX350 engine to achieve an optimized strength-to-weight ratio.

Kit Includes:

• Forged piston – aerospace alloy, CNC machined to tight tolerances (forging number 4933M)
• High-performance piston ring set – Wiseco-specific rings engineered for extended service life and sustained power output
• Alloy wrist pin – precision machined for consistent fit and reduced friction
• Circlips – retention hardware included
• Top end gasket kit – premium materials meeting or exceeding OEM sealing standards

Note: Wiseco rings are application-specific and are not interchangeable with other ring types. Wiseco pistons must be used exclusively with Wiseco rings.

Whether you're performing a routine rebuild or refreshing a high-hour engine, the PK1442 provides OEM-grade reliability with the added durability of a forged construction — all in one convenient kit.