HASTINGS Replacement Piston Rings — Bore 3.937", Piston +0.010", Displacement 107" – 18-21 Softail, 17-20 Touring, 17-20 CVO

Replacement piston ring set includes enough rings for two pistons and two rings per groove where applicable. 🔧🇺🇸

• Includes top compression rings, second compression rings, and oil control rings.
• Top compression rings are barrel face and are PVD (Physical Vapor Deposition) coated for enhanced wear resistance and heat transfer.
• Second compression rings use a Napier design; a reverse-twist ring with a taper-machined face duplicates the OD bottom-side scraping edge of a positive-twist torsional ring.
• Oil control rings are three-piece flex vent with two rails and an expander to assure positive oil control.
• The three-piece design and thin rails promote conformability to the bore, improving side sealing and oil economy.
• Helps transfer heat between the piston and cylinder wall and controls combustion chamber gases to efficiently transfer energy to the crankshaft.
• Made in the USA.