I was no good in school but C's get degrees...so I passed. A few years back probably more like 10 my Dad gave me this book and I actually was interested in Science for once. Motorcycle Science. Crazy. I still reference this book all the time when smoke comes out of my ears. It's a really basic overview on how different types of motorcycle engines run. It's always good to have some books around (Chicks will think you're smart and cultured and maybe you can learn something before you smash that Pre Unit motor into pieces.) Over and out.