Now that these bikes are really starting to get old, it becomes less common to run across mufflers in decent shape, and more common for guys to use aftermarket mufflers.
Almost invariably, every time I've gone with aftermarket mufflers, I end up with leaks at the exhaust pipe/muffler joint. This causes excessive noise, popping on deceleration, and is bad for your engine.
Original joint gaskets from Honda are basically "unobtainium" anymore, so I've been searching for something suitable to address that issue.
Found this stuff at Auto Zone - cheap, easy to use, works great.
Just used it today to cure the problem on a CB450.
A couple of turns of this fabric-like stuff around the pipe, and no more leak.
(I discarded the "activator" stuff).
I had at a sample with a propane torch for a few minutes, and it showed no damage.
Hope this helps somebody.....