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Hello All - in the final stages of resurrecting an"83 GPZ750 and can't get it to idle when warmed up. Came with Keihin CV34's and so far, during test rides, it has no problem pulling hard from low revs to red line and will idle before it's warmed up completely. Carbs have been thoroughly disassembled, cleaned with rebuild kits installed. Intake boots have been replaced with a little gasket compound used on installation for insurance. Running a pair of K&N 1 into 2 filters for intake and a cobbled together 4 into 1 header for exhaust. (PO welded a stainless Civic tuner muffler onto it) Jets are as follows (with spec as per manual in brackets) : Primary main - 65 (62), Secondary main - 115 (125), Pilot - 35 (35). Pilot screws have no effect when settings changed (starting @ 2 1/2 turns) and were re-installed with tiny O-ring in the right place. Theories: pilot too rich? Need air corrector jets? Any suggestions greatly appreciated. 

So here's where I'm at now - after reviewing the re-jetting post (Pod filter and Exhaust Re-jetting - 22 October, 2011 - Thanks Moke), I' m still confused. With 4 into 1 exhaust and pod-style filters, mods called for would be (starting at absolute stock sizes) +8 -2 :primary main = 68 (from 62), secondary main = 130/132 (from 125) and pilot 38 (from 35). With current set-up, primary - 65, secondary - 115 (smaller?) and pilot at 35, it pulls hard right into the red but won't idle worth a crap when it's warm. Also have done all I can to correct any possible air leakage concerns. Deciding whether or not to go to the effort of complete re-jetting, at the risk of messing up top end power, or concentrating on the pilot jet  to fatten up mixture at idle. Any/all suggestions welcome.  

Dynojet makes a kit with adjustable needles which will save you a lot of trial and error.

So, after significant head-scratching and developing the ability to remove the carbs in about 2 minutes, noticed that the pilot screws included with the cheap crap rebuild kits binded about 3/4 of the way in. The points of the originals, when bottomed out, protruded into the venturi ever so slightly - the ones from the rebuild kit did not make it that far. This #%&!@ sent me down the path of looking for air leakage, suspecting jetting and all other sorts of  more expensive fixes. The bike's idle is now settling down @ 2 1/2 turns of the screws and I think fine-tuning and carb synchronization should be the final trick. Moral of the story: don't rely on cheap %#@&% crap carb rebuild kits to do the job, something a lot of you probably already know. The rest of us dumb animals (aka ME) have to learn the hard way.
P.S.  - 3 turns did the trick.

Well, got the carbs all dialed in - idles great and pulls hard to well beyond where I'm comfortable taking it. One down. Only after a test ride yesterday, when it was dropping cylinders and running like crap, did I discover that the aftermarket coils were shorting out to the fuel sender on the bottom of the gas tank. As you can imagine, if there was any seepage in the area, this situation would not have ended well. What's that Nick Cage movie where he and his bike routinely bursts into flames? So, bent coil mounting brackets for better clearance from the tank and insulated plug wires at coils with sections of (new) gas line c/w zip ties - no more lightning storm under the tank. Considering, from what I've discovered from research, that this Frankenbike seems to be: an '83 ZX750 frame, '82/'83 KZ750 engine (rebuilt?) along with body parts (seat pan, fairing) from an '85 Top Gun bike along with several good and not-so-good mods/upgrades, I know that there will be more challenges in future. But, without a few posers, where's the fun? I get a sense of accomplishment knowing that I've somehow managed to create a roadworthy almost 40 year-old classic form a pile of parts. It's also fun when I get second glances from true bikers who appreciate the fact that this vintage of beast is still on the road. Putting it away for winter today (we have that in the Great White North) and awaiting what other brain teasers await me next year!