btw, if you look careful at the pictures in post #1, you'll notice that the last one, which I labeled as latest, is actually the round bowl type, the other two are square bowl types. The carburetors are taken from bikes off different years, maybe the carbs where replaced at some time, I have to look into that more closely. I'm also making a list of all small parts per carburetor, including jet sizes.
The set in picture one, post #1 cames from a '61/'62 bike, the set in picture two from a '63 bike, and the set in picture three in post #1 comes from a late '66 bike.
The '61/'62 bike is a nice example of Honda efficiency, it has parts of both years.
Frame is '62, (very early number), gastank is '61, speedo is '62, shocks has aluminum shrouds ('61), aluminum front fender ('61), seat is '62, mufflers are the short stainless steel version ('61), engine covers are '61 winker switch (optional) is typical '60 (was actually a part intended for the CB92).
It's not a Frankenstein bike (two bikes build together), I traced back the daughter of the first owner, and I saw pictures of this bike just after being bought. It's truly a factory-off Frankenstein bike, a '62, with a lot of '61 left over parts if these fitted.
30 years ago I started with collecting CB72's, the goal was to have one from each production year. The goal is accomplished, and I added this bike as an in between, on top of the '61 and '62 I own. I also have a '60 CB72 engine (almost complete) and some parts, this bike was the first one of it's kind, being brought to the Netherlands as a on-off for a yearly fair. It seems that the rest of this bike is somewhere in Belgium, at least that's how far I could trace back the history of that bike.
The story is that this bike was "lost" after the fair and went to a dealership. This dealership used the bike for racing (because this '60 bike had magnesium break hubs and a few other special parts). Soon the bike was crashed a few times during racing, and the story goes that the engine was swapped for a later one. I have this engine with a very interesting engine number, I also do have the headlight housing and the rev-speedo counter.
I took the engine apart, and found many differences when comparing with later engines. This engine has the rotating gear shift mechanism, you can change from 4th gear directly into 1st gear (and looking at the damage, this is exactly what happened at speed). The crank is build-up different, gears are the same, crankcases (sand-cast) are different (much thicker that later ones), Cylinder head side covers and top cover differ, the list goes on and on.
I gave up on completing the engine for now, because parts are very rare, if they exist.