Information on JD's

[danf19]

Not sure what category of Harley Davidson this belongs in but I am trying to find out more about the JD's I believe they were made from '21 to '29 . I believe there are significant differences between the years for the engine, mounts etc. I have latter model frame and wondering what the major differences are ? Can anyone make a recommendations in terms of a reference book ???
Again, my apologies if this doesn't belong here.
thanks
Dan

[MMasa]

Dan
Technically speaking, a "JD" is a 74 cubic inch, battery/generator ignition, inlet over exhaust (IOE) model. These were in fact produced from 1921 - 1929. However, the term JD is also more widely used to generically refer to all IOE Harley models produced from 1915 - 1929 regardless if they were 61", 74", electric, or magneto.
At this time, the best reference on these years is an out of print book called "Inside Harley Davidson". While it does have a number of errors on this year range, it is generally sound as a basic reference. Copies come up from time to time on eBay and usually sell for around $100-$150.
Another option is to ask specific questions here. I think that you will find this group to be quite helpful. What are you looking to do? Are you thinking about getting a JD as a project?
Mark Masa