I did the same and found a big improvement
My tires were really worn, so I decided to take the plunge and replace them. I bought metzelers, i think thats how you spell it me 880's i think. They are a world of difference to the stock bridgestones that I had on to start. Handling much better, and kind of felt more loose at first but I think that it was just the difference in the tires. They handle much better than the old ones. Now just to get a little softer ride...
Tires make all the difference and I like the metzelers / Brake them in , They wont feel loose once you do....
I just got me a 2000 Roadstar 1600 and I had the same thought s about vibrations. I used to ride a KZ1000(bored to 1100) and it didn't even start to buzz till you were around 8k rpm. I got the star and at 65mph I felt like I was riding over cobblestone streets, then my buddy told me it has a lot to do with those 2 (almost 4") pistons coming up together on the same stroke, I told YEP that WOULD have a lot to do with it. I'd never ridden a big V twin before..
Xnawjlfr(CHUCK)
HAHA! My last bike (for 16 years) was a KZP1000 ex-CHiPs bike. Nice wall-O-motor! Really comes alive at about 5500 RPM, under that it's a cruiser, over that it's a freakin liter Ninja with saddlebags!
My bike now is a 1700 carbed Roadstar & it takes me back to my days riding my FLH Panheads (57 & 66), only nothing falls off the Roadie. It's definitely got the POTATO THUMP goin' on! ;D
I have dealt with that for the past 6 years. Is this a problem? No I don't think so, it is a thing called vibration. Perhaps a r6 or 1 may be in your future if you don't like vibration.