Four. ADVr and ADVb are the ones I spend the most time on. I am also on the Motorcycle Alabama forum but it is nearly dead with one or two posts per day. I occasionally look and post on the Kymco Forum.
probably more than 10.
When I find a bike I'm interested in I'll usually join the forum and find out what problems to look for, see what people found that works and what doesn't.
But there are only about 3 that I visit regularly.
Adventure Rider - Perma banned but rejoined several times, currently have new alias
Two Wheeled Texans
Triumph Bobber Forum
I was part of the VFR Discussion forum for years as well as some GROM forum but I haven't visited either in several years. I am technically part of the AF1 forum but I never post there. I just go look at their inventory thread.
ADV Rider is the only place I have ever been banned from.