Coming back from a 60 mile, almost non-stop ride yesterday when the bike started bucking, farting huge backfires and shutting down. This happened when I hit traffic at slower speeds and a couple of lights. Was fine during the non-stop run, but wouldn't hold an idle at traffic lights, had to hold the throttle to keep from stalling. switched the petcock to Prime, no help. Have almost 1/2 tank of gas, so that's ruled out

Got home and noticed a huge amount of exhaust soot on the case just in front of the left front peg. I'll be looking at the exhaust header bolts tomorrow when I have the day off, and also examining the exhaust system from head back to the Trapp.

But really, I think my good luck streak with this bike may be at an end. My guess is exhaust valve issue. But, my bike did get knocked over last week. Best hope is that something got knocked out of place causing the leak

Any opinions greatly appreciated.

Because of the proximity to the tip over,... I'd guess a piece of gunk in the floatbowl, either plugged a jet, or got stuck under the float needle seat...
The black sooting points to the needle seat...

Pull the carb bottom and clean in there...

Well it's quite a reach to say the loose header will cause soot on the case near the footpeg.  Any damage to the exhaust system from the tip over?  The header shell is just that, a thin shell.  It could have a small leak and the real problem is a busted inner tube.  Could've sepparated at the header and pulled out at the supertrapp.  so it's worth looking at.

I'd go with Sero on this, more likely the tip over moved the dirt around and it found its way to the carb finally.  So you know the drill... clean it or seafoam it.