1976 KZ400 Carbs

Hello all, I have a 76’ kz400 I picked up recently. I was able to get it running with a pair of carbs from a 77’. It sat dormant for 10 years (5k original miles). My question is.. what is the best or affordable pair of carbs to use on the bike? I saw an equivalent on summit racing for Mikuni VM30-83’s. Will this work? Thank you in advance! 

What is wrong with the 77's you have now ?
 

I have a feeling they need to be tuned and also the push & pull throttle cable do not match exactly right. I’m only using the pull cable currently. I want to know how to tune them or get them running so the bike is not lean or rich. 

People here will be able to help you with that and it's probably easier and cheaper than starting with something completely different. A good starting point would be to strip them, give them a detailed clean and replace any rubber components ("O" rings, manifolds etc) 

I was thinking the same thing but I still need a set for my other 76’ as well. The current one I’m working on is in better shape so I feel like a new set would be nice in my opinion! How can I find the help? Attached a photo for reference - Looks the same on the other side as well. 

RetroRipper wrote:

I was thinking the same thing but I still need a set for my other 76’ as well. The current one I’m working on is in better shape so I feel like a new set would be nice in my opinion! How can I find the help? Attached a photo for reference - Looks the same on the other side as well. 

Doesn't look like there are any clamps on the intake rubbers so that won't help - the ones you showed from Summit require a "split" throttle cable (like on 2-strokes) I think would be a PITA to get running right IMHO

Yes I need clamps and the throttle cable isn’t a big deal for me. Just smells rich at idle. 

RetroRipper wrote:

How can I find the help? . 

You just did! Post a question, somebody answers.

Also, the Filebase here at KZR contains quite a bit of good info. For example--

www.kzrider.com/filebase-alias/category/...l-carburetor?start=0

There is also a section of the Filebase specifically for the KZ400 that includes a copy of the factory service manual.
www.kzrider.com/filebase-alias/category/11-kz400

Thank you! If you see the carb photo, which is my fuel mix/ pilot screw?

The brass screw circled in red is the pilot mixture screw. There is one on each carburetor. 
it is one of the last adjustments to do when tuning the bike. Several things can cause a rich idle mixture and all the others need to be taken care of first.  Trying to use the mixture screws to mask some other problems will lead to increasing frustration and sadness.

 

It's easier and cheaper to clean up the stock carburetors and use those than to start from scratch with something else. Yours look like they are in decent shape so even a quick overhaul of the important parts will get them working nice without fully disassembling them. Clean the outside with soapy water and a toothbrush then open up the float bowls. Clean inside and spray carb cleaner through all the passages. No need to replace any of the jets unless they are super plugged or damaged but you should remove them and clean inside. It's brass so handle with care. Two small but important parts are the pilot screw o-ring (#30 in the attached diagram) and pilot plug (#38). Parts for these are easy enough to find at places like ebay and z1enterprises etc. 
Float level is another thing that makes a big difference. I used isopropyl alcohol and some vinyl tubing to check and adjust mine on the table before installing them. Isopropyl has a close enough specific gravity to gasoline for something like this and it's safer/less fumes when working with it.
You'll also want to do a bench sync at a minimum, that will get them close enough but you should still check them with a vacuum gauge after it's running. 
Here's a link to the manual if you don't have it already  kzrider.com/filebase-alias/download/11-k...1-kz-400-shop-manual
It's a lot of small projects and time consuming but its a good learning experience, at least it was for me. Or you can order a pair of VM30's with pod filters, tune them, and after about $500 have something that performs a little bit better than stock.