Wiseco 40123M08300 Piston Kit Bore Compression - 83.00mm 12 1 YFM350

The Wiseco 40123M08300 is a high-performance forged piston kit designed for Yamaha YFM350 ATV and powersports applications. Built to a 12:1 compression ratio with a standard 83.00mm bore, this kit delivers a significant performance upgrade over factory cast pistons while maintaining reliable, long-term durability.

Each piston is forged from a high-silicon aluminum alloy, providing exceptional strength-to-weight ratio and resistance to the heat and stress of high-performance engine operation. Wiseco's innovative forging design and optimized piston skirt geometry are engineered to maximize horsepower and torque output.

Kit Specifications:

• Bore (Standard): 83.00mm
• Bore (Actual): 83.00mm
• Compression Ratio: 12:1
• Sizing: Standard Bore (STD)
• Displacement: 357cc
• Stroke: 64.50mm

Kit Includes:

• Forged piston
• Piston rings
• Wrist pin
• Circlips

Wiseco is the only U.S. manufacturer to forge its own powersports pistons in-house, using state-of-the-art CNC machining and 3D design software to produce race-proven components trusted by top competitors worldwide. Note: Gasket kit is not included. Oversize pistons require cylinder sleeving.