A piston ring (12) includes a body portion (36) presenting a running surface (44), and a spring member (38) disposed between the body portion (36) and a ring groove (28) of a piston (10). A running surface of the piston ring presents an upper rail (50), a lower rail (52), and a fulcrum (54) disposed between the rails (50, 52) and each extending radially outwardly. An outermost tip (60) of the fulcrum (54) is disposed radially outwardly relative to an outermost surface of the rails (50, 52), and the running surface (44) presents a convex shape along the fulcrum (54).The fulcrum contacts an oil film (14) applied to a cylinder (16) wall as the piston (10) reciprocates along the cylinder wall. The spring member (38) presses the body portion (36) of the piston ring (12) toward the cylinder (16) wall and causes the body portion (36) to pivot about the fulcrum (54) to provide for improved control of the oil film (14), less friction, and reduced oil consumption.
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