S&S CYCLE MK136 BLACK EDITION ENGINE FOR OIL-COOLED M8

The MK136 Engine represents the pinnacle of high-performance engineering for M8 platforms, delivering massive displacement and unmatched power without compromising the stock engine height. Designed for riders who demand elite performance, this engine is meticulously crafted to provide superior cooling, lubrication, and structural integrity.

At the heart of the MK136 are high-flow cylinder heads equipped with premium seats, guides, valves, springs, and seals. These heads feature +1.00 mm oversized intake and exhaust valves, which are 0.030" longer than stock to optimize valvetrain geometry. With a 0.605" max lift valve spring and enlarged cooling passages around the exhaust seats, these heads are built to handle extreme thermal loads while maintaining peak efficiency.

The crankcase is engineered for maximum durability and oil management. It features patented dual-spray piston cooling jets and a precision-machined oil scraper. The enlarged oil sump and contoured floor design ensure oil easily drains back to the sump, preventing power-robbing windage. To further enhance performance, each engine includes S&S performance oil pump and cam support plate, premium tappets, and tappet cuffs.

Premium Features and Specifications:

• Forged pistons for increased strength and longevity.
• Gear drive camshafts for precise timing and reduced maintenance.
• Billet aluminum covers and a custom cam cover badge.
• Includes sprocket shaft spacer and Champion spark plugs.
• S&S exclusive breather boxes for superior ventilation.
• Retains stock engine height for seamless installation.

Built with pride in the USA, the MK136 series offers configurations suitable for various applications, ranging from 49-state compliant setups to race-only, closed-course competition versions. Whether you are looking for explosive torque or high-RPM horsepower, this engine provides the ultimate foundation for your M8 powertrain.