Just like American Motocycling Magazine can be read on Google Books, the much recommended racing motorcycle series by Mick Walker are also available with one exception of the British one.
Italian Racing Motorcycles:
http://books.google.com/books?id=CNsRN9L5BYsC&printsec=frontcover&dq=motorcycles&hl=da&ei=GRFWTMTWF-eiOPrUwZ4O&sa=X&oi=book_result&ct=result&resnum=8&ved=0CFAQ6AEwBzgU#v=onepage&q&f=true
European Racing Motorcycles:
http://books.google.com/books?id=7bGuud7_uy0C&printsec=frontcover&dq=motorcycles&hl=da&ei=phFWTM1zj5c456aNnw4&sa=X&oi=book_result&ct=result&resnum=5&ved=0CEEQ6AEwBDgo#v=onepage&q&f=true
Japanese Grand Prix Racing Motorcyles:
http://books.google.com/books?id=fpoF0PMZEjEC&printsec=frontcover&dq=motorcycles&hl=da&ei=phFWTM1zj5c456aNnw4&sa=X&oi=book_result&ct=result&resnum=6&ved=0CEYQ6AEwBTgo#v=onepage&q&f=true
German Racing Motorcycles:
http://books.google.com/books?id=t5StUPaN3jkC&printsec=frontcover&dq=Mick+Walker&hl=da&ei=jRJWTLrhH8ijOPT1-J0O&sa=X&oi=book_result&ct=result&resnum=3&ved=0CDYQ6AEwAg#v=onepage&q&f=false