Jetting KZ750 E1 1980 Pods and 4-1

I start of with my current jetting (previous owner done this and it aint right)
Low speed (Pilot jet?) 32 (weird since OEM is 35 if I remember correctly)
Main jet (middle) 65 (oem then)
Secondary main jet 150

I run KN pods and a noname 4-1 exhaust
The bike is a KZ750 E1 from 1980

The troubles I have now is when I go WOT from low rews it will blur then I have to back of the throttle and try again when the revs are up it will usualy go then but I think it can be better.
It get worse when I pull the choke.
The spark plugs are black with a white side electrode (belive it to be to lean on low speeds and to rich at high speeds)

It seems impossible to set the pilot screws correctly as well since I can't hear any change in revs no matter what I do.
Can be a bad ear as well.
I have set them all at the same now at about 1 3/4 turn from bottom.
Seems to be the best setting (numerous test rides)

And I have a weird problem whit my idle.
Cold = very low idle and when warm high idle (about 1.000rpm) the idle set screw is out all the way and the throttle cable is adjusted correctly (actually a little to loose just to be on the safe side)

What I believe my self is that the secondary main jet is to large = rich condition at WOT.
My main to be on the small side
and my low speed to be way to lean.

What jetting should be appropriate for this combo?

Low speed 38 ?
Main jet (Middle) 70 ?
Secondary main 135?

That is just my first guess.
I have the OEM needle N01A I belive.

Last but not least does anyone know what size drill bit the dynojet kit use to enlarge the vacuum port in the throttle? thinking about doing this my self :evil:

Best regards Emil

For years WiredGeorge recommended using this jetting for pods and 4-1 exhaust:

Low speed #35
Main Jet #70
Secondary main jet #140

I wonder where in the world the PO get those #38 low speed jets since everything appart from #35 is supposed to be like "unobtanium".

That sounds like a good place to start.
Where do you buy the main jet?
I can't seem to find it anywhere.

The only thing I can find is the secondary main.

What do you think about drilling out the vacuum port on the throttle like you do with the dynojet kit?
And what size drill bit should I use?

Where PO got the low speed jet is a mystery to me as well.

Best regards

Btw what jetting should I use when I mount my bs34 carbs instead of the keihin?
Best regards H (who found his keihin jets on Z1 and has since bought and misplaced them, not found them yet btw)

Sorry I am not following you...
Did you get the Keihin jets? Have you try them?

Drilling the vacuum port is for quicker response of the diaphragm. However I wouldn't do it. You can't go back if it doesn't work and vacuum slides ar no longer available from Kawasaki. It is better to get some used vacumm slide springs and cut some coils.
Again: do it at your own risk. It may work, or not.

Well when i started this thread i had keihins in mind, and got good reply regardiing what jets to use.
Today however i am gonna get a rack of carbs for next to nothing (Mikuni BS34)
And am wondering what kind of jets i should use in the mikuni.

The jets i ordered for the keihins i got and Before i could try them on i missplaced them and haven't found them since.

Since i am moving to BS34 i kinda have lost intrest in the keihins anyway but i am gonna test out a set of low speed jets since i have promised to do so in Another thread.

So back to the question at hand, what jetting should i use on my Kawasaki kz750 E1 1980 whith pods and a 4-1 exhaust using a set of mikuni BS34?

Best regards H