Trying to tune my carbs?

I have an 81 KZ550 with TK carbs. Running Pods with a 4-1 After Market Exhaust. Timing is set with a light and is spot on. I'm currently running 125 mains 32 pilots with the mixture screws 1.25 turns out. Needle clips are in the second notch from the top. Its running hot around 310 on each cylinder. A plug chop on a constant 50 mph speed has t tips white. So its running lean. I've already tried 110, 120 & 125 mains. Then I've moved the clips from the top notch to the second down. Do I need to continue to move the clips down or go up again on the mains?

There are others here who know more about the TK carbs and the 550s than I do. But in my way of thinking running at 50 mph you are no where near 3/4 to WOT so are most likely looking at needle adjustments. IMHO the second notch from the clip end of the needle is pretty lean. Off the top of my head I do not know that the stock setting was, but that appears to be a lean setting to me.

I know that Lou has a bunch of info on his pages about the TK carbs and the 550s as well a many other very interesting things, but I just read about his needing to find another location to keep / host this info and currently do not know the outcome.

I am sure he will add in his knowledge here.

Well thats what I was thinking because I didn't notice much of change between the 120 and 125 jets. The needle change made a little so I'm going to move the needles again. After all it is the easiest change to make.

125 is more rich than any jetting I've ever tried, even on a GPZ. I recently jetted my friends KZ550 A, with pods and Mac 4-into-1, and the best setting was actually stock jets and stock needle with a 0.6mm shim under the needle clip. (This was using a wideband o2 sensor, not seat of pants jetting).

Plug chops only show anything if the jetting is really far off. Once the jetting is close to being good and clean, the plugs take a long time to take on their final color.

Without a wideband, you can use the Dynojet jetting guide to figure out your jetting. It's kind of generic, and not specific to the TK22, but is a good general guide to a jetting beginner.
home.comcast.net/~loudgpz/GPZweb/TK22mai...tKit/TK22jetKit.html
(Ignore the fact that the Dynojet kit comes with a 98 main, as the needle is a very different shape.)

50 MPH cruising is around 1/16th throttle on a 550, and ideally you want it to be slightly lean there.

Be mindful of your vent hoses. If they are exposed to a stream of moving air, they can develop a vacuum which will make the mixture go very lean, as it puts the bowl into a vacuum condition. Make sure the hoses come together somewhere high near the middle of the bike, Right under the back of the tank is usually good. Secure them so they don't flop around.

How hot should the cylinders be running. With the above conditions I'm getting readings of 330 to 350 degrees with an infared heat gun. The Vent hoses are tucked up inside the frame back bone. I've already tried 110's with the needles all the way up and it was still running lean. Thats why I started going up on the mains looking for more fuel. The bike runs good zero bogging or sputtering even at wide open throttle. Its got to be close!

If the needles are all the way up, something is wrong. Either the needles are shaped wrong or there is a fuel starvation issue. What needles are you running? Do you have a photo of the kit?

The needles aren't all the way up. If I have the clips in the second slot down from the top then they are almost all the way down. I can raise them two or three more slots. I don't remember off hand how many more there are.

Clip closer to the pointy end is richer.

But here you said you had them all the way up and it was still running lean?

lhemrick wrote: ... I've already tried 110's with the needles all the way up and it was still running lean. ...

Is that correct? or did you mean something else?

No thats what I meant. At that time that was what I was running. I am now up to 125 mains with the needle clips in the second slot from the top. This morning I moved the needle clips down one more slot which is the third from the top. It seems to have corrected the lean condition a good bit, no more white on the tips. I now have a slight bog when you try to throttle really hard. Maybe the 125's are to much after all and maybe I need to go back down on the mains and raise the needles further. By the way I'm running Keihin jets in these TK carbs.