Wiseco 40011M07900 Forged Piston Kit Compression Honda - 79.00mm 13.5 1 CRF250R

The Wiseco 40011M07900 is a high-performance forged piston kit delivering a 79.00mm bore and 13.5:1 compression ratio for the Honda CRF250R. Engineered, forged, and machined in the USA, this kit is purpose-built for the demands of competitive motocross and off-road riding.

Wiseco's 4-stroke forged pistons are designed for each specific engine application and built to the tightest tolerances for the ultimate combination of performance and strength. The forged aluminum construction offers superior tensile strength, an optimized strength-to-weight ratio, and improved heat transfer compared to cast alternatives — making it the choice for racers and enthusiasts who demand reliability under extreme conditions.

Key Features:

• Forged aluminum construction — superior strength, reduced weight, and improved heat transfer over cast pistons
• 79.00mm bore diameter with 13.5:1 compression ratio
• Dedicated forging optimized for this specific application's strength-to-weight ratio
• CNC diamond-turned finish ensures precise sizing with no variation, compatible with cast iron, chrome, Nikasil, and boron composite cylinder bores
• Race-ready dome finish with smooth edges for improved combustion chamber flow
• Engineered and manufactured in the USA at Wiseco's facility in Mentor, OH
• Complete kit — includes forged piston, high-performance ring set, alloy wrist pin, and circlips

Wiseco's wide range of oversize options also makes it possible to restore worn cylinder bores back to service. Replacement cylinder sleeves are available to allow chrome, Nikasil, and boron composite cylinders to be resleeved and accept Wiseco oversize pistons. Part number 40011M07900.