An old good running restored CB750 is fun to ride. The sound can bring old since long (35-40 years) forgotten memories to my mind! 
I often ask myself during the rides what use I can have of a modern multipowered bike that quickly reach 250 km/h and just continue.......
The fun roads with beautiful views I ride on will not allow that speed. On some parts is 160 km/h possible which my K2 enter quick enough, my K6 even quicker with less need of gearing down.
(Some straights +190 when I could not release the K6 throttle in time 
)
Thoughts about wild animals and dizzy car drivers usually make me to release to a more relaxing 70-100km/h.
On the country side can a tractor with a wide plow and similar wide murder tool suddenly pop-up behind next bend. Or spread chunks of clay on the road.
Typical time to be extra careful is spring and fall. Plus late summer early fall during the harvest.
I like the upright sitting position to enjoy the sceneries better.
A few top speed tests for fun to verify everything is properly adjusted.
Even if one of my CB750's will run beyond 200km/h rather quick, the normal cruising rides will be within 70-120km/h with occasional 160km/h.
Thanks Per, as much as I love riding my K0 modern bikes are fantastic too, they handle much better, stop way quicker, and accelerate much faster. You don't need to ride them at warp speed to enjoy them, but if I was riding at 200 KPH and I had to stop or swerve in an emergency situation, I'd much rather be doing it on a modern bike with 4 or 6 piston twin calipers as opposed to shiny stainless steel CB750 units that seem to go faster when you apply the wimpy single puck brake at speed in the wet, which is another reason that I'll be riding my more modern bikes as our weather turns cooler.
Both of my Triumph Rocket III's have "Upright" sitting positions, but will do 0-100 KPH in under 3 seconds, so fantastic for overtaking long lines of cars, and have great brakes (no ABS) and the last ride I did with Spotty was great fun, he was on my (now ex) FJR1300 with similar BHP, so we could ride at an enjoyable pace, and just whip around cars full of rubber-neckers.
Having said that, I'm surprised at how good the front brake on the K0 is? It is probably the best brake I've had on a CB750 and I don't know why, I put a rebuild kit in the OEM MC, am using 50 year old rubber lines, a new piston seal and new organic pads, but it feels really good? Not as good obviously as any of my modern bikes, but it pulls up really well. I wonder if they changed the material that they made the K0 disc rotors from when they went to the K1 and later rotors? I can't think of any other reason why it stops so well?
Anyway, I need to go out and put my K2 bitsa engine together, as I want to take it for a couple of shakedown rides before I pass it on to Dion as part of the Harley trade. Dion is going to repaint the bike for me as he has to remove the 1 percenter club stuff anyway, so it's going from satin black to gloss black, so should look nice.
