1984 GPz750 Running Issue

Just bought this bike in pieces, I have put her back together and got her running. Though, she will only run on a choke. Now, before you say clean the carburetor's they have been cleaned twice. They look new inside. I also checked the intakes for a leak and could not find one.My question is multi-fold;
1. The jetting looks stock, I am waiting on the factory manual as I had to order it from out of the country.Does anyone know the jet sizes are for this model?

2. The previous owner had killed the air box. Literally, cracks and holes drilled in it with the air filters cut and thrown away. It will run under choke but as soon as it as I warm her up she will die out, if I drop the choke. Can this be the jetting alone? Are the BS34's this sensitive? I don't have filters yet but I did have the carbs synched. Do I need to get filters to keep her running as well?

3. I have a four into one Dennis Kirk exhaust and I think I will run pods (Japanese air filter lingo?). What jetting have you found that works with that?

Can anyone help out, I am at a loss, at this point I really could use some help. Thanks, Roger

maybe a vacuum leak

I'd say sync the carbs, and yes you will need to rejet for the pods and pipe. Base 120-122.5 mains, middle clip on the needle, stock pilots. go from there, but that should get it running well enough to start tuning.

I doubt you will get it running very well at all without the airbox on, with stock jetting and a 4-1 pipe.

Carbs are dirty, clean em.

Pilot jets and/or circuits are plugged. Hold them up to light and see if you can see thru them. I use guitar string on mine gently. It comes in a bunch of sizes and is very cheap. Theres a blind circuit that runs from the pilot jet hole to where the idle fuel mixture screws go as well as out to the air jets on the back {airbox} side of the carbs too that can get blocked. By blind I mean you have to use the guitar strings from both directions to clean it out, spray with carb cleaner & blow out wiith air. Long frustrating story how I found that out, No amount of soaking will do it either

Thank you everyone, well since everyone stated clean, I will clean them a third time. Are pods a good idea? Or should I spring for a new air box? I am looking to make this a daily rider not a hot rod. Thanks again, Roger

i would stick with an air box

Ive run my 82 GPZ750 with an air box since new with no problems. The only bike I have with pods is my 1105 78 with 29mm smoothbores on it. If you want to run pods get a dynojet kit, Id run the airbox myself

What would you recommend for the jetting with the stock box but a four into one exhaust?

It currently has:
37.5 Pilot Jets
117.5 Main Jets

I found a stock Box at:
www.kneedraggers.com/oem-parts/KAWASAKI/1984/GPZ-750-_-ZX750
Part# 11010 B

Thanks for everyones help, I appreciate it, Roger

im running 118 mains and 37.5 pilots with 4in1 pipe and stock air box.

Hello everyone, Thanks for the help so far. I thoroughly cleaned the carbs again but to no avail, it only idled while choked. I did get my manual in the mail I see that the previous owner did re-jet the the main. I think I am going to do a rebuild at this point because APF didn't have any parts in stock. only complete bs34's. If i rebuild them should I use parts from z1?

I tried getting the air-box but when I ordered it kneedraggers.com realized that they never had it. I have now searched online to no avail. Any suggestions?

Got mine on fleabay. It along with factory jetting in my bs34s worked. I did have my old carb to airbox boots and they were a real pain to install. Love to talk more, but I gotta spend some time with my newborn son! He is amazing!