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The bike is a 1985 CB450sc. The carb is not the original so im not sure if it is pre1984 or later. SErial number is vb22gatj. i guess im a little confused on how to set the fuel mixture. I set the idle adjustment screw to 1200rpm. the Fuel mixture screws were turned 2 3/4 at beginning according to FSM. I kept adjusting fuel mixture screw till i saw an rpm drop of 100 rpm then left it there. I then adjusted the idle adjustment screw to 1200 rpm again and then started on the other fuel mixture screw till i saw another 100 rpm drop. Im getting the feeling that i did this incorrectly. I cant adjust the idle screw really either way no without an rpm drop which is a little weird i think. I cant adjust the screw any higher and now it is sitting steady at around 900rpm. Seems to be running pretty well though, it will stall out a little after a high throttle. Im assuming this is because of the low idle? Any ideas?
 

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I'm not aware of the VB22G but it's from a 1983/84 model so that's fine. It'll have the same basic operations as all the VB series carbs.
So set you idle speed to 1200 with the engine hot from riding and on the center stand.
Pick a carb and adjust the mixture to highest idle, you'll probably have to reset the idle speed back to 1200 while doing this. It can never be over 1300. Once the 1st carb is set repeat on the other one. Repeat this process one more time and go ride for a few miles. Recheck it one more time and you're done.
I'm assuming here that the sync has been already checked and set. If not then that has to be done before the mixtures
 
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