I decided to remove my pipes during my latest maintenance. Upon refitting, I made sure to put a really healthy coat of high temp RTV on both headers and mufflers. I also let it cure 24 hours before running the motor or tightening the ring clamps (much longer than when I originally put the pipes on, due to wanting to get on and ride!)
Decel popping is now virtually gone. I haven't changed anything else (jets, # / turns on screws, etc) so this is the only thing I can think would have helped. When I took the pipes off, I did notice that each had a good amount of RTV left except about 1/4 of the circumference of each, where there was no RTV and it was really black / sooty.
I know this has been suggested as a source, but I just wanted to let y'all know it does seem to help to have a good seal...plus it's only a rainy day's worth of downtime to test.
