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 2017+ Harley M8 engines, featuring a 4.320-inch bore that bolts onto stock crankcases without machine work. Black Granite powder coat finish with matching highlights delivers a substantial displacement increase while maintaining factory engine height.

Features

• 4.320 in. bore increases displacement significantly
• Works with stock crankcases — no machine work required
• Black Granite powder coat finish matches factory
• MLS multi-layered steel head gaskets included
• Retains stock engine height
• Includes Cubic Inch cam cover badge
• Made in USA

Specifications

• Brand: S&S Cycle
• Manufacturer Part #: 910-0847A
• Bore: 4.320 in.
• Finish: Black Granite with highlight
• Weight: 29.75 lb
• Category: Engine Components / Piston Sets - Powersports

Fitment

Fits Harley-Davidson 2017 and newer M8 models with stock crankcases.

Frequently Asked Questions

Will this work on my stock M8 crankcase without machine work?

Yes — the kit is engineered to bolt directly onto your factory crankcase with no modifications required.

Does this require engine tuning after installation?

A fuel and ignition tune is strongly recommended to optimize power and drivability with the larger displacement.

What's included in the kit?

Cylinders, pistons, piston rings, wrist pins, MLS head gaskets, and the Cubic Inch cam cover badge.

Will this raise my engine height or change my bike's stance?

No — the kit is designed to retain stock engine height so your bike's geometry and stance remain unchanged.