Should one wish to know everything there is to know about the development and evolution of the Norton Manx, this is not the book to have. 
When I finally got to the point of purchasing a featherbed Manx- something I had longed to do for 25 years- I bought this book in order to know more about Manxes before I bought one.

After reading this drivel, a mixture of old racing stories, vague technical information, useless chitchat, and the compulsory free promotion of various characters involved in the procurement of Manx spares of a quality that in some cases borders on the criminal, I knew little more about Manxes than before. And I knew very little about them to start with!

One can not expect miracles from an author who wrote several books a year on all marques, periods and models. However, for the money this mine of useless information has cost, I definitely expected a better return. Unfortunately, a decent book about cammy Nortons has not been written to date and probably never will. My advice is: Don't buy one, or get a copy of "Norton Singles" by Roy Bacon, which is about as good on Manxes plus gives you technical data and covers the other singles, too!

As "Big Frank" Westworth wrote about this book in CBG years ago: "It is a book I could put down, never to take it up again!" 

I think this is a fair judgement.