Just a thought.... the front heat shield mount seems really loose. Would that cause some more rattling?

Good eye! 

That heat shield might be 99% of the rattle!

Nice catch, I also noticed that and held on to it and it didn't change the noise hardly at all, to my despair.

That sounds similar to what my CT-1 sounded like when I first got it running. Sounded like something was loose, like nuts and bolts rattling around. The first time I removed the left cover found one of the case bolts underneath it was loose, the most forward one. It was completely loose, just rattling around. Once I tightened it up that noise was gone, and I was left with the usual two-stroke noise. Also, the asbestos string inside the exhaust flange was completely gone, so the exhaust pipe was rattling around in the flange. I made some orange RTV spaghetti strings, stuffed it into the flange then mounted the exhaust, and that worked, also reducing exhaust noise from the front of the engine. Before I did that, the pipe was shaking back and forth, now it stays still.

Interesting about that bolt being loose! I'll have to take a look under there. I have to fic the clutch cable anyway. Also, the exhaust is pretty loos, I held that steady and didnt get rid of much of the noise either but for sure something that needs fixing.

Despite the engine noise and various other small things I couldnt resist bringing it to the cabin over the weekend. It had no issues on the gravel roads and through the woods. It sure is a blast to ride these old machines.

   Pics

Looks good. Front tyre looks fat--but looks good like that--is it one size bigger like 325.

I'm not sure the size on it but it is definitely bigger than stock. Its been on there a while too as its cracked so I'll have to get it changed out to match the new rear tire. I like the look of it as well.