This is a good book and the only one of its kind of which I am aware. On that basis, I can recommend it heartily. However, there is plenty of room for improvement in future editions. Most obviously, the balance of coverage needs to be tipped in the direction of 4-strokes. At present there is a 4-stroke chapter, but it follows three longer chapters on 2-strokes engines and repairs. The other serious weakness, in my view, is the lack of a complete and detailed index. The publisher cut more than a few corners here. There are tons of missing entries: tire, tire pressure, tire selection, tire mounting ... just to give one example. And some entries are silly: "two-stroke engine" with two pages cited, despite the fact that there are three chapters relating to the subject. But all that said, there is plenty of really useful information in the book. The chapter on tuning tips, for instance, is wonderful, as is the extensive range of illustrations.