Topic: 1978 honda cb750k carb rebuild help

[drmeloh]

im going to rebuild the carbs on my bike, i have single pod filters on them and i found out that i have to adjust the Main jet #120, idle jets #42 and  one turn out on the mixture screw, also the i have to add shims to the needle. BUT do the pilot jet and main jet need anything in order for the carbs to get a good mix ratio of gas/air?

[Stev-o]

You can't adjust the jets

[drmeloh]

so they just need to be cleaned and put back the way they were?

[lucky]

Language problem Stev-O.


"Im going to rebuild the carbs on my bike, i have single pod filters on them and i found out that i have to adjust the Main jet #120, idle jets #42 and  one turn out on the mixture screw, also the i have to add shims to the needle. BUT do the pilot jet and main jet need anything in order for the carbs to get a good mix ratio of gas/air?"

Yes that is right. A main jet is just a solid piece of brass with a hole in it. There is no adjustment.

To get the right air/gas mixture you will need to put washers under the slide needle .
The project may be too difficult for your skill level.

I think you should put the stock air filter back on the bike.
4 into 1 MAC exhaust no muffler.
Main jets #120mm
Idle jets #42mm
Needle stock. non adjustable.
Mixture 1 turn out.

After you do that you need to sync the carbs and it will all work very well with that exhaust.

[Stev-o]

Language problem Stev-O.

Yeah, guess I don't speak California?!

[Stev-o]

so they just need to be cleaned and put back the way they were?

First, do you know what size jets you have? If they are the wrong size, you can change them. And yes, they need to be very clean to work properly.

[lucky]

The OP has not reported in on the accelerator pump system condition and function at all.

I explained it and how to check it in detail. no response on that yet.

[lucky]

Hope we hear back from Drmeloh. Otherwise what a waste of time eh?

[drmeloh]

ok everything you guys said sounds good.
i dont know what is the size of the jets, i havent touched the carbs at all. im trying to collect as many info as i can first so then i can manage to do it properly.

[harisuluv]

Ok well, first collect the info on the carbs you want rebuilt 

[Stev-o]

Send your carbs to Haris!

[drmeloh]

well i check the manuel and the main jet is #120 and slow jet is #40.
float height should be 26mm.
im sure thats what they are, the previous owner said he cleaned the carbs but didnt say he changed anything.

[Stev-o]

Don't ever believe what the PO tells you!