Haynes, 1999. 229 p.Preface. Introduction. The cylinder head. Porting and cylinder scavenging. The exhaust. Carburation. Ignition. The bottom end. Lubrication and cooling. Power measurement and gearing. Appendix I - Introduction. A Motocross modifications. B Enduro modifications. C Road race modifications. Appendix II - Table of useful equivalents. Appendix III - Speciality suppliers. Index.