New to forum 1982 CB750 C pic attached

[fixnmybike]

Hi,

I purchased my bike in the fall, and have since pretty much refinished the bike. I have attached few pictures of it.

Does anyone know about the carbs to this bike. I was thinking about sizing the main jets a little bigger to help aspiration.

Thanks, and hope you enjoy the pics:





Will post more upon request.

[woodsrider250-2]

Nice paint!  How is the engine running in a negative fashion?

[fixnmybike]

Thanks,

Although you can't see it in the pic, the orange has a ton of pearl in it. It really pops in the sun.

Actually the engine for all intensive purposes is running perfectly. The pod filters on the carbs make it breath better, I was hoping by stepping up in jet sizes I could get alot more mid-high range power.

I'd like some feedback from people that have actually performed this mod. What kind of results they may have gotten, and what size, and manufacturer of the jets they used.

Thanks again for the kind words on the paint!

[woodsrider250-2]

Well, I'd have to say you're lucky it's running well with stock carbs and pods period...I mean running decent in the least.  The recommendation for pods (from people smarter/more experienced than myself) is to run the K&N stage III jet kit....The important thing from the kit is the needles, and they aren't available seperately anywhere, and possibly no actual main jet changes will be needed.  Upping the primary main a size or two (from 68 to 72-75) is a good general jetting fix too as aparently it was too lean from the factory for emmissions.

[fixnmybike]

I've heard the same thing as far as running to lean.

Will look into the K&N

Thanks

[gonebiking-2]

Here in Australia emission controls didnt come into effect until the the 1980s which means that my 1980 CB750K has no emission control junk on it. Which therefore doesnt restrict the engines capabilty to rev into and over the redline - its easy to do, if you dont watch the tacho when you open the throttle from a standing start. However I have never been game enough to fiddle with these intricate carbs, as they perform flawlessly and have only been fully overhauled once in their lifetime, and still work perfectly well to this very day. I did change the rear sprocket from 44 teeth ( Standard fitment in OZ )back in the very early days to a 40 toothed sprocket, and while it may not be a sprinter off the start line, I get much better fuel consumption, and at 110 KMH the rev counter reading has dropped by a 1000 rpm and seems to stay in the 4000 RPM rev range quite happily between 110 -130 KMH. At 5000 RPM the speedo is indicating close to 145 KMH !!! And thats more than fast enough for me at my age.

[woodsrider250-2]

No emmissions control junk was on them here, but the primary mains (ala midrange jet) came lean to pass a more stringent epa sniff at the time.  Would be curious to know what primary mains the OZ bikes came with.  a 72/75 replacing the 68 will eliminate a small lean bog most will have stock (US bike)

[fixnmybike]

On another forum, I read a thread about drilling hole in the inner exhaust tube to create a more open throaty sound. Not only making it sound better but creating more mid-range torque.

These mods were performed on cb750's nighthawks. exhaust was 4 into 2. Four holes were drilled in each pipe.

With my bike having 4 to 4 exhaust. That would mean I'd drill 2 holes per pie, and get about the same results? Can anyone comment?

[fixnmybike]

On another forum, I read a thread about drilling hole in the inner exhaust tube to create a more open throaty sound. Not only making it sound better but creating more mid-range torque.

These mods were performed on cb750's nighthawks. exhaust was 4 into 2. Four holes were drilled in each pipe.

With my bike having 4 to 4 exhaust. That would mean I'd drill 2 holes per pie, and get about the same results? Can anyone comment?

[fixnmybike]

On another forum, I read a thread about drilling hole in the inner exhaust tube to create a more open throaty sound. Not only making it sound better but creating more mid-range torque.

These mods were performed on cb750's nighthawks. exhaust was 4 into 2. Four holes were drilled in each pipe.

With my bike having 4 to 4 exhaust. That would mean I'd drill 2 holes per pie, and get about the same results? Can anyone comment?

[gonebiking-2]

In Australia the CB750K had/has a 65 primary jet and if my old memory serves me right the CB750F had different jets and was  slighly quicker than the 750K - but not having owned a 750F I dont know what jets were used in those bikes.

[DWightSperber]

Nice bike. Wish mine was in the shape that yours was before you painted her. In the pick you have up I don't see the back rest back on the bike. would you be interested in selling it?

[fixnmybike]

Hi, Thanks for the comment. Everything is for sale! I really didn't know what I had. I see some of these forums, and people really love these older honda's.

I will be making my own backrest, as the factory one doesn't tickle my fancy.
Mechanics on the bike are 100% It has 40,000 miles on it
If you are interested in knowing more shoot me your E-mail, and I'll send you some more pics.

The bike is in Ohio