variations on the vm26??

Hey everyone Im working on my 77 650 b1. having some issues with the carbs.
engine has just been rebuilt, and on going through the carbs that were on the bike, the carb body on the #4 was really pitted and damaged. It looked like someone had overdone the acid bath or something. Anyway, I gave it a shot, but could not get the #4 clyinder to run correctly. So I figured that I would just get another body for that one and save the $$ of buying a new set.
Anyway, I got a beat up old set on fleabay that looked like it had what I needed. So I got the ebay body onto my set, and still having trouble with that same #4.
Bike will idle, but #4 is not firing. Pipe does not get hot. If I rev it up it will heat up, but not nearly as hot as the other 3.
Also, if I start it up and just let it idle, then check the plug, it is wet with gas.
#4 cylinder has good spark, and compression, and float level is ok, checked with clear tube.
So I am thinking that #4 is over rich. (make sense?)
So I go to look at the air/fuel screw.
The new body does not have one!??
There is a hole in the same location as the other bodies, but there are no threads inside for the adjuster screw, and there is no hole that goes through to the carb throat. Just a blind whole. All of the bodies from the ebay set are like this.
Please see the pics. there is another difference between the two. there is a small brass tube in the intake throat on the new set that is not on the set that was with the bike. (see pic)
Is it even possible to make these slightly different carbs work together?
They are all called out as vm26 for 77 kz650, but there are definately differences. Is there any way to call these out more precisly so that I can avoid this while looking for another carb body?
And does anyone out there have a body for vm26 that does have the a/f mixture screw?

Thanks in advance for any and all help.

KZ650 had VM24s.(VM22s on earlly models?)
Carb with the brass tube is off of a set of accelerator carbs.
Someone has a mismatch set of carbs.
Use the whole set of the e-bay carbs.

unfortunately that set is not complete. I bought it just for the body that I thought that I needed.
The set does not have the accell pump, but I guess that someone could have taken it off. All four carbs are missing the bowls, so maybe the pump went with the bowls.

Do the carbs with the accell pump usually have a/f adjustment screws in the same location? Or am crazy in seeing that these dont. (maybe a/f is adjusted by a different mechanism?)

Also, I think you are correct, they are 24's

thanks for the help.

Just to check the vm24s or the vm22s have ribs on the exterior of upper carb body, while vm26s do not.

As to pilot screws - some of the vm24s assemblies have a fuel pilot screw located on the engine side of the bowl, while other assemblies have the air pilot screw located on the side of the carb near the air intake, and yet some others have both types. Are you sure there is no air screw, as some of the air pilot screw carbs have a plug covering the actual air screw. The plug has to be removed to see the screw.

IIRC all of the vm style carbs used on the 605s have ID #s stamped on the engine side flange near the choke handle and on the same flange on the outside of #4 carb. IIRC this is the carb assembly part#. If you provide the numbers on your carb I may be able to provide more info as to what you have.

dg4now, thanks alot for the info. Ill check tonight for the #'s.
These carb bodies do have the ribs.
Ill also measure the inside dia, but im pretty sure that they are 24's
-the original set that I started with has the air pilot screws near the motor side.
in the attached pic. its the one with the brass screw. the ones that I got from ebay have the hole in the same location, but it is just a blind hole. No threads, and no pinhole thru to the carb throat.
Do the ones that have the air pilot screw on the side near the air intake have plugs from the factory? I think this is what I have.

Im goin home now, so Ill take a look and post what I find.

Thanks again.
MJ

Ok I have attached a pic of vm22s and vm24s. The 24s are on top and the 22s are on the bottom. This paticular set of 24s has an accelator pump, the 22s do not. Note that one way to tell them apart is the VM22s have an aditional vent like opening in the carb air intake, it is located at about 10 o'clock that the 24s do not have. You can also measure them, pull the slide all the way up or remove it and measure the throat where the slide intersects it. You can do a quick check by using a scocket that is larger than 22mm but smaller than 24mm. If it fits it is a 24, if not it is a 22.

From what you have described it sounds like your orginal carbs have the fuel pilot screw, and the one new one does not have this screw, rather it has an air pilot screw. I have never mixed and matched the 2 different types of carbs in a set. So I can not say if you will be able to tune them alike or not. You could always use the jets, slides and bowl bottoms from the orginal carbs on the newly aquired carb bodies so all have the same type of pilot adjustment. I have attached other pic of the air screw plug.