What is the term used when a piston has reached the top of its stroke?

The term used when a piston has reached the top of its stroke is "TDC," which stands for Top Dead Center. At TDC, the piston is positioned at its highest point in the cylinder, marking the end of the compression stroke within a four-stroke engine cycle. This position is crucial because it influences the timing for fuel and air intake and ignition, as the engine reaches its maximum compression before the power stroke begins. Understanding TDC is essential for anyone working with small engines, as it affects adjustments and repairs related to the cranking and combustion processes.

The other terms presented are related to engine mechanics but do not signify the same position as TDC. BDC refers to Bottom Dead Center, which is when the piston is at its lowest point. Full Stroke describes the entire movement of the piston from TDC to BDC but doesn't specifically indicate when the piston reaches the top. Crank Angle refers to the position of the crankshaft in degrees, which aids in understanding the engine cycle, but does not directly denote the position of the piston at its highest point.