Hmmm!...

I recently received an assortment of parts from a trade deal, that included a set of '76-'77 era airscrew 26mm Mikuni's from a 900/1000 model. They were basically thrown in with the parts lot. The dude said he never could get them to run right,. I was good with that, with the intent to eventually take 'em apart for a looksee and a good cleaning and keep for a spare set, since I have 3 bikes of that size and era. Anyway today I opened them up for a looksee. Well it wasn't long before 2 abnormalities popped right up in plain sight!

#1) There was 2 different size main jets! Inside 2 were 118's and outside 2 were 115's LOL. Hmmmm.
#2 I took out the pilot jets and this (the attached pic) is how they came out! *Top ones in the pic are new and bottom jets are what came out* Double-Hmmmm!

I'm not the brightest bulb in the chandelier and never claimed to be, but that just ain't right lol. I've been riding and wrenching on these bikes since my H.S. days back in the mid-70's, and this the 1st time I have ever seen a pilot jet come out like that...much less 3 of the same set! Anyhow a bright light and magnifying glass indicates the rest of those jets are up in the orifices. I could not shake or jiggle them out. Now to figure out how to get the pieces out. Perhaps a shot of cleaner to try and dislodge the pieces.
Has anyone else ever seen this happen? Some input would be cool. Thanks
P.S. That carb set was basically a freebie with the other parts. But if I can save 'em and bring 'em back to life?...That would be a big plus in my book. Too bad I won't be seeing that dude again, or I'd show him 2 reasons why he couldn't get them to run right.

The main Jets are aftermarket also. No good comes with that. I’d break them down and soak them in carb dip. Hopefully that will free up the broken parts. Be patient those carbs are fetching good money today. 

My guess was a gummed up system at some point from sitting too long when last opened or altered. They came out easy w/o forcing them, so apparently they were already broken for whatever reason. Yep a complete disassembly and proper dip and cleaning is in the works. I have all new kits on hand for whatever needs replaced. Hopefully the floats are fine. I've never had to replace a float, so don't have extras. I treat all old 45+ year old parts with TLC, because yes, replacement (quality) parts can get spendy. Thanks, and keep the wind behind you.

Those carbs were only used in 1976 and in my opinion were the best of the big bike carbs in that era.  In 1977 they added pilot fuel adjusters and plugged the fuel/air screw holes.  I have a set on my 1980 KZ1000 and really like them.  Easy to work on and easy to synchronize.  You might try a shot of compressed air to loosen those broken pilots.  Or you might dislodge them with a small wire from the hole in the carb throat.

Having larger main jets in carbs two and three is not that unusual, especially on air cooled engines. Even the more modern water cooled ZRX1200 came that way from the factory.

A bath in an ultrasonic cleaner might loosen those jet parts. 

Multiple soakings, squirts of cleaner and reverse blasts of air through those passageways failed to dislodge the broken stuck P-jet ends. I know they're in there because new jets won't insert far enough for the threads to catch in 3 of the 4 openings when trying to insert a full length jet. Good news is the passages are not blocked because air flows through the passageways. My guess is that they would work if reinserted after unclogging the jets themselves, which supports the bad gas theory. So a test fire is in the works. We'll see.

Have you tried a very small drill bit operated by hand? It may be enough to just bite into them and pull them out with a pair of needle nose. 

Thanks. That thought was actually next on my list, but I don't have a bit tiny enough at the moment. I'm curious though as to what that tiny pipe extension of those pilot jets actually do, because I've no idea what that passageway looks like. I'm guessing they're the same size regardless what size the jet bores are. Meanwhile I have them cleaned up, back together and ready to mount up to my project bike for a experimental test fire. So off to my shop I go lol.

That tiny pipe (with the holes in the air flow) is made for to suck fuel from the cab bowl over tiny pilot air vaccum port (venturi effect) and mix the fuel/air ratio for the pilot circuit. Please correct me if i am wrong. My native German language to English translation and gramma sounds sometimes a little strange at complex explanations...

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That tiny pipe (with the holes in the air flow) is made for to suck fuel from the cab bowl over tiny pilot air vaccum port (venturi effect) and mix the fuel/air ratio for the pilot circuit. Please correct me if i am wrong. My native German language to English translation and gramma sounds sometimes a little strange at complex explanations... Thanks! I assumed it was for mixing the fuel/air for the idle/low end. I just wanted a 2ns opinion to confirm my suspicions. 

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 I'm curious though as to what that tiny pipe extension of those pilot jets actually do, because I've no idea what that passageway looks like. 

The factory service manual includes theory of operation and detailed diagrams for all the carb internal passages and circuits.

Here is the diagram from the ZK1000 manual.  The pilot system includes an air inlet that mixes air and fuel together as it passes up into the internal passages.  Those holes are where they mix.