a lollypop is a washer that pivots open and closed on a shaft... so that it partially blocks airflow, and reduces noise...
It's no substitute for a real baffle... if it was, all mufflers would have them, because it would be cheaper and easier... (heck,.. we wouldn't even have mufflers... just restricted, exhaust tubes)...
A lolly would be difficult in a Dyna muffler, because it has a baffle chamber... (the pivot shaft would have to go through it)...
I did have the baffle plate (a solid plate in the middle of the Dyna muff).. blow out on my bike... and to temporarily fix it,... I hammered a huge nut into the center of the chamber...
It was still way too loud, so I threaded a bolt into the nut... That helped a lot...
... but, still too loud for me... so I got a new muff...
(plus,.. I was a bit afraid that I might shoot somebody if I backfired)...

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Lollipop's are bootlegger tech... they would run quiet in town, and open up if chased...
... or that's the story I heard...
... but,... they really don't flow like a muffler should,... and wide open, they will probably burn out an exhaust valve...
... a bootlegger didn't care... as long as he got away...
Supertrapp's are basically lollipop tech... no flow, just an adjustable blockage...

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