2M6482040 3-7/16" bore chr/moly piston ring set. +.040"

These .040 inch oversize Hastings chrome-moly piston rings are designed for 1941 to early 1978 1200cc Big Twin engines. When a cylinder requires significant boring to clean up wear, these rings provide the necessary seal for a 3-7/16 inch base bore. The set features 1.6mm compression rings and a 4.75mm oil ring, sold as a pair for both cylinders. The chrome-moly material ensures a long service life and excellent seating characteristics. As a tech tip, always measure the height of your piston grooves to ensure these rings, which feature a standard 1.6mm and 4.75mm profile, are the correct match for your pistons.