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

S&S Cycle front cylinder for 2017+ Harley Milwaukee-Eight models, finished in wrinkle black with polished highlight. A 4.250-inch bore displacement upgrade designed to bolt onto stock M8 cases for increased cubic inches and horsepower.

Features

• 4.250 inch bore front cylinder
• 2017+ Milwaukee-Eight (M8) compatibility
• Wrinkle black finish with polished highlight
• Ready to pair with S&S pistons and gaskets

Specifications

• Brand: S&S Cycle
• Manufacturer Part #: 910-0675
• Bore Size: 4.250 inches
• Position: Front cylinder
• Weight: 11.83 lb
• Finish: Wrinkle black with highlight

Fitment

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

Frequently Asked Questions

What size piston do I need with this cylinder?

Pair this with S&S pistons and ring sets sized for 4.250-inch bore. Check S&S part compatibility charts for your displacement target.

Will this fit my Twin Cam engine?

No — this cylinder is exclusive to 2017+ Milwaukee-Eight (M8) models. Twin Cam engines use different S&S cylinder kits.

Is machine work on the cases required?

Always have a qualified machine shop inspect and hone your M8 cases before installing new cylinders to ensure proper fit and ring seal.

What displacement does a 4.250-inch bore give me?

Combined with the M8 stroke, a 4.250-inch bore typically yields 110-117 cubic inches depending on final configuration and piston selection.