Wiseco 4552M07900 Forged Piston Kit Yamaha Oversize - 79.00mm 10.25 1 FJ1100/FJ1200 XJR1200 2.00mm

The Wiseco 4552M07900 is a forged high-performance piston kit designed for Yamaha FJ1100, FJ1200, and XJR1200 engines. This is a 2.00mm oversize kit delivering a 79.00mm bore diameter at a 10.25:1 compression ratio, making it an ideal choice for engine rebuilds requiring cylinder boring or sleeving. Each piston is forged from high-silicon aluminum alloy and engineered to the tightest tolerances for the optimal combination of strength and performance.

Key Features:

• 79.00mm bore diameter — 2.00mm oversize for use with bored or sleeved cylinders
• 10.25:1 compression ratio for strong power output
• Forged from high-silicon aluminum alloy for superior strength and thermal stability
• Dedicated forging design optimizes the strength-to-weight ratio for each specific engine
• Improved tensile strength extends piston service life under high-performance conditions
• Innovative piston skirt design promotes maximum horsepower and torque
• Kit includes: piston, 3110XG ring set, wrist pin, and circlips
• Engineered, forged, and machined in the USA in Mentor, OH

Important Installation Note: This oversize piston requires cylinder boring or engine sleeve installation prior to fitment. Professional machine work is recommended to achieve proper bore clearance.

Wiseco piston kits are proven across every level of street and performance riding, delivering the power and reliability demanded by serious motorcycle enthusiasts rebuilding the iconic Yamaha FJ-series inline-four engine.