Join Date: Jun 2009
Location: Gaithersburg, MD
SOLUTION: Two years later, I finally had some extra time to work on my VTX. Combination of two things, although I think it was principally #2. I do still detect an occassional low, rumbing backfire, similar to what I can hear on my 2017 Indian Roadmaster.
#1, I pulled out the carb just enough to not require disconnecting the water hoses. Dropped the float chamber, opened and cleaned the fuel pump and vacuum diaphragms, both the main and idle jets. Blew out all the fuel pathways with compressed air. Cleaned out all varnish.
#2, I also found that the petcock diaphram had ruptured, resulting in drawing fuel into the vacuum line. I replaced the entire petcock assembly for about $112. In my uneducated, layperson opinion, This is what most likely was causing extra fuel getting into my system and going KAPOW in my pipes almost every time I decelerated.