Petersen's insight makes technical issues understandable even to the motorcycle novice. In easy-to-understand language, Donny examines what's right, what's wrong, what's "just okay" about the Twin Cam power train.

This is the first volume of Petersen's long-awaited Donny's Unauthorized Technical Guide to Harley Davidson 1936-2008. This twelve-volume series by the dean of motorcycle technology will examine the theory, design, and practical aspects of his subject.

Donny has studied privately with Harley-Davidson engineers, plus, he's worked on Harleys for over 35 years, having founded Toronto's Heavy Duty Cycles in 1974, North America's premier motorcycle shop.

Having ridden hundreds of H-D Flatheads, Knuckleheads, Pans, Shovels, Evos, and Twin Cams across four continents-doing all of his own roadside repairs-Donny has acquired the practical knowledge what lets him share street-wise tips, as well as walk you through detailed service procedures like porting and polishing cylinder heads to performing simple maintenance like oil changes.

Donny Petersen is honored to share the wealth of his motorcycle knowledge and technical expertise.