S&S MK136B BLACK EDITION ENGINES

S&S MK136B BLACK EDITION ENGINES

S&S Cycle is proud to announce the launch of the MK136B Engine (Part #310-1295, Race Only Model), the latest evolution in complete crate engines designed specifically for 2018–2024 H-D® Softail® Models. Known for delivering unmatched power and reliability, S&S has once again raised the bar with a motor that combines massive displacement, innovative engineering, and legendary craftsmanship.

Built from the foundation of the MKB-Series crankcases, the MK136B mates 136” cylinders and flywheels with high-flow cylinder heads, +1mm oversized valves, and .605” valve springs. The result is one of the largest, most powerful, and most dependable crate engines available today.

For riders seeking street-legal performance, the MK136B is also available in a 49-State Compliant Model (Part #310-1296).

High-Flow Cylinder Heads

  • Premium seats, guides, valves, springs, and seals

  • +1mm oversized intake and exhaust valves

  • .030” longer valves for improved valvetrain geometry

  • .605” max lift valve springs

  • High-strength alloy casting for superior durability at high temps

  • S&S exclusive breather boxes

Precision Crankcase Engineering

  • Patented Dual-Spray Piston Cooling Jets

  • Enlarged oil sump with precision-machined scraper

  • Contoured floor for optimized oil return

  • Premium-quality components throughout

MK136B Performance Package

  • Forged pistons

  • S&S performance oil pump and cam support plate

  • Premium tappets and tappet cuffs

  • Billet aluminum covers with sprocket shaft spacer included

  • Champion spark plugs

  • Retains stock engine height for seamless installation

  • Includes cam cover badge

  • Powder coat finish matched to factory look

  • Massive displacement = massive power gains

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