TOPIC:

Hello everyone,
I'm new to the forum. I have a 1981 kz650 f1, I tried to fix the carburetors but with a not very good result, not being able to find all the original pieces. I wanted to ask you what type of carburetors could replace the originals. I was thinking about those a gpz 750. Someone has already done it and what modifications need to be made. thanks in advance to all...

What needs to be fixed on your old carburetors?

Does your bike have CV carbs, or VM's?  As I understand it, with the later year 650's, Kawasaki went to Mikuni BS32 CV type carbs. 

One option would be standard issue VM24's, which are plentiful on eBay.  The GPz750 used BS34 CV type carbs, so a little larger.  I don't know what would be involved with making them fit on a 650.  Carb and airbox boots would most likely need to be changed.

BTW, I've got a set of restored GPz750 carbs if you are interested.

Hi, in US, 81 650’s had vm24 pumpers, CSR’s in 82 went to bs32’s, Don’t believe F1 was sold here (Canada? And Europe?)32’s and 34’s have same external measurements, will need to swap rubber on both sides to switch to BS carbs, and single cable throttle, have installed on my 81 650csr,

VM24 carburetors would be the simplest option as they should be a direct fit. possible issue would be you may need to swap throttle cables if the cable mount bracket is different (?) in which case you might be able to swap your bracket.

When switching to BS carburetors, in addition to different carb holders & ducts, you'll need to get a different airbox or recut the holes in the stock airbox. Someone on another forum did the latter when he installed ZR7/ZR750 carburetors; the topic is gone & it wasn't easy peasy but I forget. 

An airbox that should work with era BS carburetors should be one from a KZ650H-CSR or the KZ750E/H models >> all of them are embossed w KZ750 E\H.  For other 750 models compare the donor to your stock airbox. some of them such as the shaft drive models are shaped differently at the shoulders & I have no idea how they'd fit.

ps: in case you find some cheap ZR carbs. I don't know if any of the airboxes mentioned would fit the ZR7 carburetors. the hombre who recut the holes was from Argentina, so getting a replacement was problematic. 
 

Used stock air box, air ducts obtained from Cruzin Image in Japan, listed under 750, intakes from partzilla, carbs from Marty in Buffalo, BS32’s for Kawasaki, not many around, vm24’s are plentiful

It is possible that the original carbs are fixable, but without additional information we may never know.

hello everyone, my bike fit vm24...i really dont know what part doesn't work properly cause i replaced almost everything .i took the bike to a mechanic but , he changed again some part , the last one were the pipe bleed (impossible to find,impossible to find but in the end i succeeded even if used).Anyway,the bike doesn't run properly.
For this reason i wanted changed for something easier to find .
i tried to find on ebay as you suggested me , but i don't find nothing.
My carbs are in attachments.thanks everyone...

 

My carbs are vm24ss, i tried to fix i replaced almost all part.The last part i replaced were the blide pipe (p/n 49122-1006 Impossible  to find but in the end i found it, of course used).
I took the bike to a mechanic ,for the tuning of carbs but i told me the carbs got some little problem cause all the parts are not the original one and something else.At low rpm i got a loose of power , when the rpm  increase looks better. Also when the engine it's cold turn on it's very difficult, need a lot of time and battery.He suggested me to find something new or different that can  fit on kz650, also cause for the vm24 its difficult to find the spare parts..tried on ebay and all around the web,but i didn't find anything.I just found something for pitbike(vm24).
Anyway, here attacched a picture of m carbs.
thnk everybody

Those carbs look beautiful.  What sort of problems is the bike experiencing?  Maybe the problems are not carb related?  Have you checked the valve clearances, and is there  good solid spark on each cylinder.

If you are in the USA, I'd say send the carbs to me, and I'll tell you what's going on with them.  I suspect you are not stateside, though.

If you have replaced the internal brass with anything other than original Mikuni or Keyster parts you should remove it and re install the originals.
Unless physically damaged the original brass should be retained and the only parts these carbs usually need are 'o' rings, gaskets, choke plunger seals, float valves and sometimes the fuel mixture screws if the tips are broken.
I've rebuilt hundred of these carbs and have had no problem getting them all to function correctly once thoroughly cleaned out .
These VM carbs are some of the simplest and most reliable you can get and swapping them out for something else shouldn't be needed.
 

Thanks for your suggest....where i can find on web mikuni or keyster parts?In Italy or in Europe is really difficult.