A slider-crank mechanism includes a slider, a shaft, and a drive train correlating reciprocation of the slider with continuous rotation of the shaft. The slider reciprocates along a slider axis with respect to a slider surface. The drive train includes a linear actuator connected to the slider for substantially pure collinear movement with the slider to substantially eliminate side forces between the slider and slider surface. The slider and drive train may include a rack-and-pinion configuration. The rack-and-pinion may drive or be driven by a Grashofian four-bar crank-rocker linkage that includes a rocker arm, floating link, web, and the shaft. The slider-crank mechanism may be employed in a power generation system such as an internal combustion engine or a power consuming system such as a compressor or pump.