The Web site is a little disorganized. They do tell you what you have to do to become a member. Southern California Motorcycling Association SCMA is an association of motorcycle riders. They list events, runs, and associated clubs. Southern Cruisers National organization with numerous state chapters.
All brands are welcome.
No dues, no work. Just ride safe. Free membership unless you want a patch. Has a forum on Delphi. The STOC is an Internet based association devoted to the Honda ST1100 with worldwide membership.