Hi Don i fully understand & appreciate the sound you are talking about , was only young in the sixties when the 250 Honda six , Benellis , etc where in the prime of there racing era however i have heard the sounds & they are with out doubt awesome , i agree open pipes on the current bikes would be brill , however we know that health & safety & do gooders wont allow this .
My own personal favourite sound to this day is standing at the top of Bray Hill on a clear sunny night & listening to the BMW Rennsport sidecars making there way out through Union Mills superb , the engine notes give away every twitch of the outfit .
I also have a recording of Florian Camathias going in & out of Governors when he had the Gilera motor in his sidecar wow , mind blowing .
Sound is good & the sound of all todays machines is more or less the same but i suppose we have to live with that .
Anyway talking hard of hearing i am only 44 & have two hearing aids , listened to to much Punk Rock music when young , even more reason for them to turn the exhausts up . Cheers Shaun.