The book "Triumph 3- and 4-Cylinder" by Matthew Coombs is a comprehensive reference work for motorcycle enthusiasts and mechanics dealing with the maintenance and repair of Triumph motorcycles. It covers a variety of models, including the 750 Trident, 900 Speed Triple, and 1200 Daytona, and provides detailed instructions on maintenance tasks, repairs, as well as removal and installation processes. The information is clearly structured and includes all necessary procedures and dimensions essential for independent maintenance. This book is a valuable resource for anyone looking to maintain their motorcycle themselves and gain a better understanding of how their vehicles work. It is aimed at both experienced mechanics and hobbyists who wish to enhance their skills in working with Triumph motorcycles.