A piston is provided for an internal combustion engine. The piston may include a cylindrical first piston portion having a first diameter, a cylindrical second piston portion of the first diameter, and a cylindrical third piston portion of a second diameter less than the first diameter located between the first piston portion and the second piston portion. The first piston portion may be configured such that prior to assembly, the first piston portion is separate from the second piston portion. The piston may also include a continuous, gapless piston ring circumscribing the third piston portion, where the piston ring may be configured such that when heated the piston ring deforms in an axial direction of the piston.