new to me 1978 KZ 1000

hardrockminer wrote:

The mystery deepens.  I wonder if the valve is opening and closing correctly...as already mentioned...how is the clearance? 

If you have another carb or a rack of carbs you could try them to see if that helps.

I can't remember if I wrote them down. But I do remember they were all nicely in spec. There wasn't any that were " well it's close enough"
We have a big swap meet coming up on the 23rd, in Red Deer.  I will be checking it out. 
 

If the plug get wet you have spark and comp it may be fuel not atomizing at all. Check that tip on mixturescrew is not broke off or bent. You also mentioned something about the small o rings on micturescrews earlier maybe  one is bad?Check that fuel level is not too high floding You can adjust the float height/fuel level with the carbs in bike.It is a little fiddely but easyer than pulling the carbs .Afterall you have pulled and cleaned the carbs twice so that should be good .  You can also try to swap mixturescrews and se if problem move.

Thanks Rolf
I'll check the mixture screw. I know it's not broken, I checked that for sure. Maybe bent, I'll check it again. 
I know it has a small scratch about an 1/8" down from the tip.
I replaced the o-rings from a kit I got from Nessism. I'll check it also.
I was going to do some gut swapping. To see if I can figure out what the heck.
I checked the float levels a couple times as well. It's sitting at 4mm below the carb body, at the bottom of the meniscus.
I just walked away from the ole girl for a day or two. Just a little PO'd. So I started replacing the woodbed on my 81 GMC stepside.

As the plot thickens or the stomach churns!
I inspected the pilot screw. Not bent or anything. 
But I swapped it with a different carb, and no change/fire.
I was able to swap carbs with #4.
Now cylinder #2 runs perfect, and nothing on #4.
so now we know it’s in the carb!
We know it’s getting gas, because the plug is wet and the carb holder is wet as well. When I pulled the carbs off.
So it must be flooding!?
Float level checks out at 4mm at the bottom of the meniscus and no gas coming out of the over flow.
so the float should be good, no hole in it.
I’m starting to lean toward a faulty starter plugger. But wow it has to be dumping a pile of fuel, for it not to fire.
A friend suggested that I just go get another used carb and clean and rebuild it.
But I’ve put so much time and effort into this dumb thing, that it’s almost become an obsession!

It may not feel like it but you are making progress

Ok one more thing you can do is check that the float valve needle dont leak. You can use your mouth and blow into the fuelhose es .If you are able to blow the
float valve needle seat is leaking .When float height is set to low so the fuel level is too high the fuel should come out of overflow tube ,but sometimes it does not and drible into combustion camber and down in engine.

Wookie and someone else said it had to be in the pilot or starter plunger.
so that's where I went next.

Well, I think got er figured out!
It's the pilot jet.
I swapped #2 and #4 back to their proper places.
Took apart #2 again and checked the starter plunger/choke. And compared it with carb #1.
Nothing different.
I then took out the pilot jets and compared them.
I could see a lot more light through #2 than #1.
So I swapped only the pilot jets from #1 and #2.
Lo and behold #1 wouldn't fire.
I do recall when #2 wasn't getting any gas in the cylinder, that the pilot jet was plugged.
The tiny little wire I tried to push through would only bend.
But it was the right size for the other pilot jets.
So I went to a little stiffer but also a tiny bit heavier wire. This cleaned out the jet. But it looks like it made it too big also!
Go figure!!
So now I'll need to find a pilot jet or set of.
Thanks everybody for all the help and advice.
I'll let you know if my diagnosis was correct, when I get another jet.