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

S&S Cycle piston set for 2017 and newer Harley-Davidson Milwaukee-Eight engines, featuring 4.250 in bore x 4.500 in stroke standard sizing. Direct replacement pistons for stock or mildly modified M8 builds.

Features

• 4.250 in x 4.500 in standard bore and stroke
• Designed for 2017+ Milwaukee-Eight (M8) engines
• S&S Cycle quality construction

Specifications

• Brand: S&S Cycle
• Manufacturer Part #: 920-0140
• Weight: 3.22 lb
• Category: Engine Components / Piston Sets - Powersports

Fitment

Fits 2017 and newer Harley-Davidson Milwaukee-Eight (M8) engines.

Frequently Asked Questions

Will these fit my Twin Cam Harley?

No — this piston set is specific to Milwaukee-Eight engines only. Twin Cam builds require a different part number.

Are these stock replacement pistons or high-performance?

These are standard bore and stroke pistons designed for stock or mildly modified M8 builds.

Do I need to hone the cylinders when installing new pistons?

Yes — proper cylinder preparation is essential for piston ring seal and engine longevity. Have your cylinders honed to spec before installation.

What's the weight per piston?

The complete set weighs 3.22 lb. For individual weight specs, contact S&S Cycle directly.