First published in 1996, Eric Gorr's guide to maximizing stock motocross and off-road motorcycles and building factory race replicas has become the definitive work on the subject. This all-new edition is extensively revised to cover all bikes built from 1985 through 1999, including: the Powerjet carbureted Honda CR250 and CR125; the new Yamaha four-stroke YZ400F and WR400F; and all other new-for-1999 bikes. KTM competition bikes and the Kawasaki KLX300 four-stroke will also be covered. Step-by-step instructions and a generous selection of exclusive photography show how to maintain, modify, and set-up every component, and how to correct common flaws. Advice is also provided for buying used bikes, setting up a shop at home, and preparing for race day. Eric Gorr is a professional motocross tuner and the author of the original Motocross & Off-Road Motorcycle Performance Handbook.