Add Yahoo as a preferred source to see more of our stories on Google. The bore of a cylinder (along with the stroke and the number of cylinders in the engine) is what determines displacement.

Bigger isn't always better: here's why engine designers obsess over bore, stroke, and cylinder size.

At Circle Track we're all about tech, all the time. And at least a few times a year we'll show you how to assemble your own engine from air filter to oil pan. But one area of tech we rarely touch on ...