V4 K'nex Engine, Manageable Amount of Pieces

hey guys, i was looking around youtube and saw a single cylinder engine that was REALLY compact, so much so that I could build it rather easily, i made 4 of them and put them together into a 4-cylinder engine, it's even got a flywheel!! oh by the way the pistons weren't my idea, it was the idea of a certain youtuber named stencilwhiz heres the link to the instructional video that he made, that i used as a base idea for my engine and heres the link and oh by the way heres a video, i've also made an instructable, if you wish to see it then click on the link here. ok? ok.