Cool ideas!
Yes, the power is UP! The midrange power I was used to at 4400-5000 is now available from about 3200 up. I haven't wound it past 5500 RPM yet, it's pretty young...
I solved most of the fouling problem by raising float height to 27.5mm on the inside carbs, 28.0 on the outside ones. I need to find some 95 jets (and 90s) to sort out the final: it runs real strong at 100 size right now, using a new Honda paper air filter (while I soak my old K&N for a week or so).
The best part: the surging these engines do so often at 3500-5000 in lower gears is COMPLETELY GONE. That's the big surprise: it's much smoother in that range than it ever was. I didn't expect that. I think the spark advance curve will need a little work, though, because it snaps at about 1500-2000 something fierce, just as the clutch is letting fully out. I think I need to delay the advance start just a little to smooth that out. But, carbs first...
The discussion about plugs: top fuel dragsters and alcohol cars use 2 because they fuel them so close to hydraulic lock that one ignition miss will cost them an engine. Dirt bikes often come with 2 so one heat range (colder) can be used on the highway to the dirt, and another(hotter) in the dirt, to preserve the engine. That was Yamaha's original intent, anyway.
A better idea than multiple plugs is the approach used by racers: use multi-spark discharge. Several brands are out there, but I would have to research them to see which ones could live on a CB power budget.
BUT-this gives me a great idea: I am an electrical engineer, and designed (probably the first) transistorized ignitions for the CB750 in 1972. I built one for me and sent the plans to my friend (then in New York), who built another for his K0. It was a module that mounted on the rear fender, near the taillight (for lack of space elsewhere), and connected to the stock points. The current through the points was reduced to .1 amp, so they lasted until the rubbing blocks wore out, about 15,000 miles, and the gap was only .010", so dwell, spark voltage and bounce were all greatly improved. (The drawback here was that the slots in the points plate had to be widened to accomodate the smaller gap and still get the timing right.) The wires had to be upsized from the module to the coils to reduce losses, but the standard 7kV output was almost 11kV as a result. MPG went up, smoothness was 'WAY better, and they idled (imagine a 750 actually idling!). This setup was good for 14,000 RPM on the track, using stock points with crosses cut across the faces of the contacts to let air escape better. Later, we drilled holes thru the points, which was easier.
Today, these parts are dirt cheap (it cost $78 in 1972 to buy just the parts). So, maybe I should make some more! The Dyna systems are pretty good, but if you don't use the whole DynaIII with their coils, you only get about 6kV spark from the stock coils. (Not your high-perf arrangement), and the Dyna coils don't last like Honda's own. With a little addition to my original circuit, I could nearly double the Honda coil's kV output today, maybe even make it multi-spark. Hmmm...
Some a$$^*le stole mine off the back of my bike at a motel one night, in 1974. The only good part was, I just connected the points back to the coils, opened the gap to .014" and timed it with a 12v lamp from the instrument cluster, and kept on touring - a little delayed. Some people's kids...
