Well I've owned a 1978 Ducati 900SS, surely the sexiest bike of the era, and also the biggest heap of #$%* that God ever shovelled guts into! Sorry guys, but if you look in an Italian dictionary under unreliable, breakdown, or ulcer there's a full page pic of one of these things! The modern "Ducks" are reliable, fast, and almost as sexy as the old Desmo twins, which is probably why the company is still in business.
I had a 1975 Kawasaki Z900, it was a very fast bike in a straight line, but no-one (including the factory) could make them handle, so after spending lots of money trying, I sold it and bought a 1984 Harley Sportster that actually handled and braked better!
I think my 1981 Suzuki GS1000S "Wes Cooley Replica" is about as close as I'll get to my dream bike, it handles, brakes, and will do 140 Mph+ in standard trim, and it's super comfy for long trips. I bought it cheap and haven't spent much money on it, but it looks like a period Jap/American "Musclebike" racer and eats Z1's for breakfast!
I have loved CB750's since I first saw one in the early 1970's, and have had at least one in my garage since 1978. They are a simple, robust bike that doesn't do anything particularly well, but at the same time are a pleasure to ride, and have (I believe) the best looking engine ever built.
My "Endurance Racer" special that I am building now will be my ultimate "Dream Bike", with all the beauty and reliability of the classic 750/4 engine with a lot more power, and a chassis that will allow me to explore the upper limits of the performance spectrum. Cheers, Terry.