Answer they just do Answer Yep, they just do it.... :) I guess you're wondering how do they get an engine that's in my car, into this small bike. Well although these engines work like the one in your car, they are very different. To start with, there's only ONE cylinder, as opposed to four or eight (or whatever) in your car.
And the second big factor is that the engine in you car is at least 1 liter, probobly more. 1 Liter is 1000cc. Dirtbikes are usually up to 450cc.
There are some over 700cc but definitely not more than a liter So there you go. You have a SMALL four stroke engine, now you can put it wherever you like Answer If you go back in history a few decades, you'd that most, or nearly all offroad bikes were 4-stroke. They were heavy, and not especially fast, but then few offroad bikes were (fast).2-strokes were dirty and didn't like running at low speeds as one must when riding offroad- the sparkplugs would foul up.
Air-cooled two-strokes were prone to overheating and seizing, as well.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.