Wiseco 842M06425 GP Series 2-Stroke Piston Kit 64.25mm Bore Yamaha RZ350 Banshee

The Wiseco 842M06425 is a GP Series forged 2-stroke piston kit designed for the Yamaha RZ350 and YFZ350 Banshee. With a 64.25mm bore (+0.25mm oversize), this kit is engineered for riders who demand long service life and maximum top-end power from their two-stroke engine.

The piston crown, ring groove, and pin bore are all Electra-Coated to resist wear, combustion heat damage, and ring micro-welding. An ArmorGlide skirt coating reduces friction for optimized power delivery. Boost ports are removed for a more predictable powerband and stronger top-end pull.

Key Features:

• Bore size: 64.25mm (+0.25mm oversize)
• GP Series forged 2-stroke design for endurance and sustained-RPM applications
• Electra-Coated crown, ring groove, and pin bore for maximum wear and heat resistance
• ArmorGlide skirt coating reduces friction and optimizes performance
• Forged from high-silicon, low-expansion aluminum alloy for superior strength and reduced weight
• Engineered, forged, and machined in the USA (Mentor, OH)
• Kit includes piston, rings, wrist pin, and circlips
• Oversize bore — cylinder sleeving or overbore required

Wiseco GP Series pistons are ideal for play riders logging hard hours and competitive racers alike, delivering a reliable and powerful top-end rebuild for the Yamaha RZ350 and Banshee 350 platform.