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Hello All, I am new to this forum. I recently purchased a 1981 CM400E to rebuild. The bike runs but the carbs leak a lot of gas as soon as the gas switch valve is turned to
"run" or "res." Because of this issue, the carbs became my first project.

The carburetor is a VB 22R A UK. When I took the carbs apart, I noticed only one of the three jet holders had a jet in it. The one jet in the carb was a 120. The rubber plug and the 78 jet was missing. Interestingly, the jet holder for the 78 jet isn't threaded. I'm not sure if the holders are supposed to be empty or if someone else took these apart and forgot to replace the missing jet and plug. Both the left and right side are missing the plug and jet.

Are there supposed to be rubber plugs in both? Why is the jet holder for the 78 jet not threaded?

Any advice is welcomed.
 

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Haven't heard of VB22R carbs so I suspect this isn't a US bike. The carbs should have a Primary main jet, 78 in your case, that is screwed directly into the body in the hole closest to the mixture screw. The Secondary main jet is screwed into a brass jet holder that is then screwed into the body and is directly under the piston needle, the jet holder is actually holding the needle jet/nozzle in place in the body. The rubber plug is needed to fill the 3rd hole that's offset to one side.
Primary
201_4062.JPG
Secondary
201_4063.JPG
Rubber plug
201_4064.JPG
 

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I am having problems figuring out my carburetor as well. Its a VB22R A VCA but it came on my '78 CB400T. The plugs are missing and it was jetted to 42/105. Some places are listing the stock jetting as 70/110 with a 38 slow jet. I can't even find a third jet that would be the slow jet.
 

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It helps if we know where you are located since different countries got different models or variations on the same model.

It sounds like you have the 2 jet version of the VB22, possibly a PO retrofitted them to your bike or that's just the way they came wherever you are. How does it run?

Welcome to the group.
 
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