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

S&S Cycle front cylinder and piston kit for 2017+ Harley-Davidson Milwaukee-Eight (M8) engines, featuring a 4.250-inch bore with a matched piston. Built to OEM-quality standards for reliable performance in the modern M8 platform.

Features

• 4.250 inch bore front cylinder
• Matched piston included
• Designed for 2017+ M8 engines
• S&S Cycle OEM-quality engineering

Specifications

• Brand: S&S Cycle
• Manufacturer Part #: 910-0734
• Bore Size: 4.250 inch
• Position: Front cylinder
• Application: 2017+ Milwaukee-Eight (M8)
• Weight: 1 lb
• Category: Engine Components / Piston Sets

Fitment

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

Frequently Asked Questions

Will this fit my Twin Cam Harley?

No — this kit is engineered specifically for 2017+ Milwaukee-Eight (M8) engines. Twin Cam owners need a different S&S Cycle bore kit.

What's included in the kit?

The front cylinder assembly and a matched piston designed for the M8 platform.

Do I need a rear cylinder kit too?

This is a front cylinder kit only. Order the matching rear cylinder and piston separately if you want a full top end.

Is professional installation required?

Yes — cylinder and piston replacement is an engine teardown job requiring machine shop precision and specialized tools. Professional installation is highly recommended.