Introduction
In a four stroke engine, the pushrod transfers radial movement from the cam lobe to the rocker arms.
Additional Resources
https://en.wikipedia.org/wiki/Valvetrain#Pushrod
https://en.wikipedia.org/wiki/Overhead_valve_engine
https://www.motorcyclecruiser.com/how-to-four-stroke-internal-combustion-engine
https://www.britannica.com/technology/push-rod