[WapCar] The stroke is the distance from the top dead center to the bottom dead center of the piston.
Without considering other factors, simply looking at the size of the cylinder diameter and stroke, we can get: under the premise of the same displacement, the design of "small cylinder diameter x long stroke" will make the speed of peak torque appear lower, which is suitable for low-to-medium speed engines, and the power output is strong when starting and accelerating.
Conversely, the engine with a "large bore x short stroke" design is more suitable for high-speed engines because each piston stroke is shorter. A higher limit speed is its specialty, and if you want to start and accelerate faster, It can only be achieved by increasing the engine speed.