Wiseco Pistons 4419M08350 Forged ATV Piston Kit 0.020" Oversized for Yamaha 350cc

The Wiseco 4419M08350 is a high-performance forged piston kit designed specifically for Yamaha 350cc ATV engines. This oversized piston features a +0.020" (0.50mm) bore increase to 83.50mm, making it ideal for rebuilding worn cylinders or performance builds requiring precise bore restoration.

Why Forged Pistons Matter:

Wiseco manufactures all pistons in-house using advanced forging techniques that create a condensed, aligned grain structure throughout the material. Unlike brittle cast pistons that fail catastrophically under stress, forged pistons deliver superior toughness, impact resistance, and fatigue life—critical advantages for demanding ATV applications. Each forging is engineered to optimize the strength-to-weight ratio for maximum performance and durability.

Key Features:

• Forged from high-strength aluminum alloy for extreme durability
• 0.50mm (0.020") oversized bore: 83.50mm diameter
• Precision-machined ring grooves and skirt coating for reduced friction
• Designed to withstand high-performance and racing conditions
• Complete piston kit includes rings, wrist pin, and circlips
• Direct replacement for Yamaha 350cc ATV engines

Compatible Models:

• Yamaha YFM350 Big Bear (1987-1999)
• Yamaha YFM350 Warrior (1987-2004)
• Yamaha YFM350 Wolverine (1995-2009)
• Yamaha BW350 Big Wheel (1987-1988)
• Yamaha YFM350 Bruin (2004-2006)
• Yamaha YFM350R Raptor (2005-2010)
• Yamaha YFM350 Grizzly (2007-2010)

Wiseco's complete control over the manufacturing process—from raw materials to finished skirt coating—ensures consistent quality and performance that professional mechanics and enthusiasts trust for engine rebuilds and performance upgrades.