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Article: Introduction to the S&S Cycles MK136 Oil Cooled M8 Motor

Introduction to the S&S Cycles MK136 Oil Cooled M8 Motor

Table of Contents

  • Introduction to the S&S MK136 Black Edition
  • Technical Specifications of the MK136
  • Expected Power and Performance
  • Testimonials and Real-World Impressions
  • Installation Insights
  • Maintenance and Upkeep
  • Conclusion

    Introduction to the S&S MK136 Black Edition

    The noise of a Harley Davidson is not just any sound; it's an anthem to freedom and the thrill of the open road. For enthusiasts keen on elevating this iconic experience, the S&S Cycles MK136 Black Edition M8 Touring Motor offers a profound upgrade. This latest iteration of S&S's celebrated complete crate engines is crafted for seamless integration with 2017 and newer H-D Touring models, boosting both the machine's performance and aesthetic appeal with its striking, blacked-out design.

    Technical Specifications of the MK136

    More than just a motor, the MK136 Black Edition is a pinnacle of engineering designed for the ultimate riding experience:

    • Engine Type: Embracing Harley's V-Twin heritage, this model enhances every ride with unmatched power and a resonating pulse that motorcycle aficionados cherish.
    • Displacement: Boasting an impressive 136 cubic inches, the MK136 transforms any tour into a high-octane adventure, offering exhilarating acceleration and unparalleled torque.
    • Compression Ratio: Optimized at 11:1, this engine is tuned for both spirited sprints and enduring long-distance tours.
    • Cooling System: Its advanced oil-cooled system features enlarged cooling passages around the exhaust seats, designed to handle sustained high-performance by effectively managing thermal stress.

    Features and Benefits

    • Cylinder Heads: High-flow heads are fitted with +1mm oversized valves and .605" max lift valve springs, enhancing the engine’s breathing and efficiency. Premium materials improve durability under high temperatures.
    • Crankcase: Features patented dual-spray piston cooling jets and a precision-machined oil scraper to maintain optimal oil viscosity and engine cooling. The enlarged oil sump and contoured floor design ensure smooth oil circulation and quick drainage back to the sump, enhancing overall engine health.
    • Pistons and Camshaft: Forged pistons paired with S&S’s performance oil pump and cam support plate ensure robust engine internals capable of handling increased power outputs.

    Expected Power and Performance

    Tuned to unleash over 145 horsepower and 155 ft-lbs of torque, the MK136 Black Edition is engineered not just for raw power but for an exhilarating riding experience. The substantial increase in displacement, coupled with sophisticated fuel management, ensures potent performance complemented by efficient fuel use, making every ride thrilling and economical.

      Installation Insights

      Engineered for compatibility with 2017-2023 Harley-Davidson® M8 touring models, the installation of the MK136 Black Edition is straightforward for those familiar with engine mechanics. Key steps include:

      • Preparation: Collect all necessary tools and ensure the workspace is clean and organized.
      • Removal of Existing Engine: Carefully remove the existing engine components, taking care to protect any parts that will be reused.
      • Engine Placement: Position the MK136 engine within the frame, securing it according to the manufacturer’s specifications.
      • Component Installation: Install the additional components such as the billet aluminum covers, spark plugs, and cam cover badge. Each piece should fit seamlessly if the right preparatory steps are followed.
      • System Check and Calibration: After installation, perform a thorough system check and make any necessary calibrations to ensure optimal performance and engine integration.

      Maintenance and Upkeep

      To ensure the MK136 Black Edition performs at its best over time, regular maintenance is crucial. This includes:

      • Routine Oil Checks and Changes: Given the high-performance nature of the MK136, maintaining optimal oil quality and levels is essential.
      • Cooling System Maintenance: Regular checks of the cooling system will help prevent overheating and maintain performance efficiency.
      • Periodic Adjustments: Regular adjustments and checks of valve timing and clearances will help sustain engine performance and longevity.


      The S&S Cycles MK136 Black Edition Oil Cooled M8 Touring Motor is not just an engine—it's a significant upgrade that redefines the performance and aesthetics of your Harley Davidson. It offers a perfect blend of formidable power, refined style, and operational efficiency, ensuring that each ride is not only exhilarating but also distinctly superior. With the MK136, riders gain more than just speed; they embrace a new level of motorcycle excellence, making every journey unforgettable.

      To Shop the MK136 Motors - Click Here