1977 KZ1000LTD bogging down at WOT

Regardless of whether your jetting is correct or not, whacking the throttle wide open from any position on a slide carb will overwhelm the engine with air and always cause it to bog.
You are momentarily starving the engine of fuel because it takes a split second for the jets to react to the change in pressure through the venturi.
It is easier to produce bogging with slide carbs than CV's which is one reason why CV's are fitted to the large majority of modern bikes.
Whacking the throttle open on a CV carb does not produce the instant slide response of a slide carb due to the slide not being directly connected to the cable, the slide rises much smoother and slower in response to the engines air flow needs and the fuel supply is able to keep up in relation so the chances of bogging are reduced.

Whacking open the throttle is not a natural action when riding or even in race conditions though so why do it.

That confirms what I thought about going as fast as possible from closed to WOT. But, I cannot use WOT from low RPM's even if I roll on the throttle at a normal, or even slow, rate. It will still bog down and just stay like that until I roll off to about 3/4 or so and then the thing jerks forward and starts pulling. I cannot use WOT until the revs are up over 5-6K.

Is that normal?

I'm going to pull the carbs off again and clean them again, this time paying very close attention to the air jet and air jet passage. I believe that will be the hole on the bottom left when looking into the carb throat from the airbox side. According to the manual that passage is supposed to exit at the bleed pipe.

If anyone has any other suggestions I'm open to them.

I pulled the carbs and broke them down to the last part, even separated them off the rack. These carbs are spotless inside, passages are clear and completely unobstructed. I sprayed carb cleaner thru the pilot and main air jet passages followed up with 120# compressed air. No crud came out, they were already clean and clear. Yes, I followed the often posted pilot circuit cleaning guide. All passages are clean, I am 100% sure they are clean.

I verified the correct stock main (105) and pilot (15) jets are installed and the correct needles (5DL31-3) are installed with clip in middle (3rd) position. I ran a pipe cleaner thru the needle jets and they are clean. They do not look egged out to me. I did not remove them because I don't think there is any reason too, plus I'm not sure if they can be without damaging them. They are a canceled part from Kawasaki and I have not seen replacements.

I can rule out the carbs as being dirty. The only things I am unsure of on them would be the condition of the needle jets. Not the needles themselves, they look fine, but the needle jet. I'm also not 100% sure the top cover gaskets are sealing, I will replace those, but I doubt they are causing my problem. The fuel screws are new from Z1E, my originals were bent/broken by the PO.

I'll put the carbs back on the bike tomorrow and give it another test ride. Before the test ride I'll pull the plugs and see how they look and take a photo. I have 50 miles of mixed riding on these plugs with the stock jetting back in the carbs. These plugs (NGKB8ES) were new about 100 miles ago.

I'll also check for a fat blue spark on all 4 plugs before the test run.

FYI... Here's how I set my points.

The manual has several pages of instructions, pictures, etc. on how to set the timing using the static method plus timing light, plus dwell meter. I can give you a fairly easy way that will get you in a pretty close ballpark without a timing light or dwell meter, but you will need a 0.35 mm feeler gauge and a multi-meter or other device to test continuity. To be very precise, the timing light and dwell meter will be needed.

Remove the points cover on the right side of engine. Under it you will see 2 sets of points. The set on the left fires cylinders 1 & 4; the set on the right fires 2 & 3. When replacing points observe carefully how the little bits and pieces are arranged where the wires attach. Some of those pieces are actually insulators and if you leave any of them out or put them back in the wrong place the points will be grounded and won't work. Take a very close look at the contact surfaces of the points. If they are pitted you really should replace them. You can sand down pitted points, but they will quickly pit again. Replace one set of points at a time so you can look at the other set in case you get the little bits confused.

Use a 17 mm wrench to turn the nut NEAR the end of the crankshaft clockwise while looking in the hole above that nut. (Do NOT use a wrench on the smaller bolt on the very end of the crankshaft to turn the engine.) Inside that hole you will see a vertical pointer cast into the casing. As you turn the 17 mm nut you will see a 1 & 4 and F and T roll by and then you'll see a 2 & 3 and F and T roll by. Each F and T has a line next to it.

Here's the method I use for static timing. I turn OFF the ignition. I disconnect the green wire near one coil and the black wire near the other coil. (This is not in the book, but it makes checking continuity much easier for me.) After installing the new points or cleaning up the old ones, turn the 17 mm nut while watching the points. When points set 1&4 are at their widest gap adjust them (by loosening the 2 screws that hold the points to the backplate) so the gap equals 0.35 mm. Turn the 17 mm nut clockwise through a full revolution again and double check this gap. Then repeat this for points set 3&4. Now set your meter to test continuity and clip one wire to the leaf spring on points set 1&4 and clip the other wire to ground. Turn the 17 mm nut clockwise until the 1&4 "F" mark aligns with the pointer mentioned above. You want the continuity across point set 1&4 to just break when the F mark aligns with the pointer. The idea is that when the continuity just fails is when the points will fire their respective coil and cylinders. In order to adjust the point at which continuity fails you loosen the 3 screws that hold the backplate to the engine and slightly turn the backplate until the meter shows a break in continuity. Once you have the 1&4 set timed properly you can check the 2&3 set to make sure they break when the 2&3 F mark aligns with the pointer (they should or something is not right). Don't forget to plug in the green and black coil wires when you are done, and put a little grease on the rubbing block felt. Assuming you are using new points of the correct type this should enable you to get the timing very close. Trying this with old points may give poor results, especially if the points are pitted and/or the rubbing blocks are worn.

After you have set the gap (which in effect sets the dwell) and the timing using the method above you can use a dwell meter and timing light to fine tune dwell and timing. If you have followed the above procedure carefully, very little if any fine tuning will be needed.
Sorry this is so long. It's not as difficult as it sounds. Ed