If you need wiring diagrams for older bikes , Harley's and other model bikes also (1965- 1993) where a service manual may not be available, try here For older models... http://www.smokeriders.com/diagrams/index.php?list=Harley_Davidson/Twins Index of /specs/wire or download all wiring diagrams in one archive here. Harley Davidson Community - HDTimeline Downloads Page - 1965 - 199x Harley Davidson Wiring Diagrams Here's a few more diagrams for Big Twins and Sportsters. Go to the left side of the page and click on "TECHNICAL ARTICLES" for Big Twin and other great info. Translated version of http://www.planete-biker.com/wiring_diagrams_01.phpsa%3DG Select Technical Articles on the left of screen. Also look here for more on the older bikes... Shovel Magic - Harley Davidson Community and here... Shovelhead History - Harley Davidson Community Some of the older diagrams here... Chops Garage - Electrical Wiring Diagrams