Interestingly, the 750's primary handling 'feel' was brought about by American marketing input. The first test frames had over 4" (100mm) of trail, but a brisk discussion with guys like Bob Hansen of American Honda (among others) made the company wonder if the bike was really going to be a hiway buzzbomb, or a Saturday nite boulevard bike. The trail ended up being shortened to 3.85" on the early K0 with the shorter shocks, which became the more common 3.75" trail with the later 13" long versions. It has the shortest trail of any bike in its class, ever. This lends it a heavier feeling when you are deep in the turn and go to pull it back up: you actually have to pull it back up, while longer-trailed bikes will flip up (and over, if too exhuberant) by pulling the bars into the turn.
The tradeoff is the lighter feeling at lower speeds (if the steering bearings and swingarm bushings are good) that the Big Four always provided, compared to, say, the KZ1000 or the Z1, and especially compared to the BMW, Harley, and Brit bikes of the day.
Today, the 750 is about 100 lbs heavier than its counterparts, not counting HP. This is purely due to the tech involved, but it also provides something that folks like Ilbikes touched on: the CB750/500/550/350F all provide the "old perch" ride, where you sit atop the bike and command it with your body english. Beginning in the late 1970s, you sat "in" the bikes more (the Z1 was one of the first like this), which reduces your authority over the bike's weight, and loses the top hamper that stabilizes them on high-speed straights like US Interstates. These later bikes felt more 'lively', but also fought back when cranked over to the footpegs.
When the monoshocks were born and the ultralight castings of great strength became practical to manufacture (translation: people were willing to pay $5K+ for the bikes, as opposed to $1695 or less), the frame became more rigid and handling naturally improved from that. But, the loss then was the division of bikes into "task machines" where you kinda needed one for touring (Wings, Ventures, Beemers), one for around-town stuff (something nimble with a removable luggage rack and/or tour-pak on the back for errands), and a third one for hotrod riding.
The Fours still provide all 3 functions in one package, with at least 85% of all the other 'types' all built in. Hence, their enduring lives.
