S&S Cycle Cylinder & Piston Kits — Harley-Davidson Street Glide, Softail Fat Boy 114, Road King Special (2017-2026)

S&S Cycle cylinder and piston kit for Harley-Davidson Milwaukee-Eight (M8) engines without highlighted fins. A complete top-end assembly bolts onto stock M8 crankcases to increase displacement and compression for added power.

Features

• Complete cylinder and piston assembly
• Designed for M8 engines without highlighted fins
• Increases displacement and compression
• Bolt-on installation to stock crankcase

Specifications

• Brand: S&S Cycle
• Manufacturer Part #: 910-1009A
• Category: Engine Components / Piston Sets - Powersports
• Weight: 30 lb

Fitment

Fits Harley-Davidson Milwaukee-Eight (M8) engines without highlighted fins. Not compatible with highlighted-fin M8 block designs.

Frequently Asked Questions

Will this fit my M8 with highlighted fins?

No — this kit is designed for M8 engines without highlighted fins. A different part number is required for highlighted-fin blocks.

Do I need to remove the engine from the frame to install this kit?

Yes — cylinder and piston kits require removing the engine and separating the top end from the crankcase.

What's included in the kit?

Complete cylinders and pistons ready to assemble. You reuse your stock crankcase, cases, and internal engine parts.

Will I need to retune my fuel management after installation?

Yes — increased displacement and compression will require a fuel tune and ignition adjustment through your ECM tuner or dealer for proper operation.