Topic: Wrong carbs?

[Grumpyfck]

Just to be clear I am not particularly experienced in the art of mechanics, I  am will to learn though. What I know - registered in 82 the engine and frame are cb750 f2 sohc. I was told, also supported by the details on log book and data information inserted in the Haynes manual it came with, it has a yoshimura 812cc bore kit and YH-1 cam. Looking to attempt to service the carburetors my research leads me to believe the set is from an earlier model, they have the round barrel tops. Is this likely to give me issues? Also I am not wanting to buy incorrect service kits. I will try to not ask to may stupid questions...promise.

[bryanj]

Those are definately NOT F2 carbs but what exact model dont know

[Grumpyfck]

Indeed, The Haynes manual shows the photographed in the main section and different in the f2 additional section near the back. From my research they were used from 71 to 76. While researching I read mentions of improving older model with the newer type, so seems strange to have gone the other way with the engine mods, hence my worries.

[bryanj]

There are just about nil upjet kits for the PD carbs which are standard on the F2 and they were a very lean burn carb also notorious for blocking up especially on pilot system.
The earlier type are far easier to dial in when majour engine mods have been done, for example it is nearly impossible to get pd's to run properly with pods like you have

[Grumpyfck]

Aah, reassuring. Thank you so much! Having never heard it run it was a little concerning. It is a baffling machine with a foggy history. I can make sense of that information.

[754]

I find those easier to work on. Once the ramps on the bowl get cleaned  and maybe a smear of grease, you can pop the bowls off by hand.. waaayyyy easier than removing 3 or more screws back in where you cannot  see.
 And the jets all screw out, not so on the pilot on late carbs.
 And you can get at the idle mixture screws easy from the side  vs up underneath where you can't see and need a special tool.
 And there is less parts, less setup..
 There are a few advantages to the PD style carbs, fast idle , and a scrawny  accelerator pump system is a plus... till you have to work on it. 

[Grumpyfck]

Well I have never done it before, I appear to be missing a lock nut of the top, service kit to source etc. I am prepared to give it a go.

[Don R]

 Most often they just need a good cleaning and blow out. Many kits have inferior replacement brass so keeping those things original to the carb is often a plus.

[Grumpyfck]

Thanks for tip, I am guessing jets have been corrected for the mods,  there is information regarding a tuners. If nothing else  there hopefully is a starting point. I was thinking more seals. I do remember vaguely (it was 15 years ago!) The seller telling me of a small oil leak on the centre front dowels on the head? I suspect sourcing an 812 gasket  will be difficult and pricey. I have muchly learning in my future I think.