HASTINGS Replacement Piston Rings — Piston size +0.005", bore 3.937", displacement 107" – 18-21 Softail, 17-20 Touring, 17-20 CVO

Replacement Piston Rings provide reliable sealing and oil control for two pistons. 🛠️🇺🇸

Includes top compression rings, second compression rings, and oil control rings to ensure optimal combustion sealing and improved oil economy.

• Top compression rings are barrel face and are PVD coated for enhanced wear resistance.
• Second compression rings are Napier design with a reverse twist and taper‑machined face to duplicate the OD bottom side scraping edge of a positive twist torsional ring.
• Oil control rings are a three‑piece Flex Vent design that uses four steel rails and two expanders to provide uniform pressure and positive oil control.
• Three‑piece rail design allows better conformability to the bore for improved sealing.

Promotes heat transfer between the piston and cylinder wall and controls combustion gases so the piston can transfer energy to the crankshaft.

Includes enough rings for two pistons; two rings per groove except for the rails, which use two rail rings per one expander ring.