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Discussion Starter #1
1982 cb450 9,900 miles. I rebuilt the carbs, I put them back together at least how I thought they were when I took them apart, now the idle is at 3000ish (tach quit), the hesitation is at normal cruising throttle but if you crank on it (60% throttle) it will at first bog down and then come to life and want to buck you off of the seat. When you let off of the throttle or when it idles it will back fire.
 

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Did you only do work on the carbs?

This is a good post for other newbies to discover and learn that taking pictures of anything you take apart on a bike should be accompanied by lots of pictures of the parts as they are removed.

If you only worked on the carbs then they are possibly reassembled incorrectly with the jets in the wrong spots or the floats upside down. It could also be they are still not clean and passages or jets are still plugged. What was the reason for taking them apart originally?
 

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Discussion Starter #3
For some reason taking pictures never occurred to me even though I do it for all my other projects. As I took parts out, i.e. the jets, I put the new ones in so that I wouldn't put them in the wrong spot, if your suggestions to the cause of the problem are correct, then I suspect the carbs are still dirty. I redid the carbs due to some hesitation while accelerating and the fact that they had never been cleaned.
 

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Cleaning carbs can be a challenge to get them clean especially if the slow speed jets are clogged. It isn't recommended to replace the OEM brass jets/parts with aftermarket ones, as typically they are not up to the quality standards of the original parts. The originals are normally cleaned and reused rather than replacing them. I don't believe the replacement parts would cause the issues though unless they were really way off spec, so it maybe more of a unresolved cleaning issue or something installed incorrectly.

The VB series of carbs this bike uses should have an accelerator pump attached to the one carb bottom and that circuit can be problematic to clean and get running right. it will cause running issues if it is blocked or only partially working.

Did you follow any of the tutorials on the site in cleaning these carbs? A ultrasonic cleaner is the gold standard for getting the bodies and jets properly cleaned, yet not always an option for most part time hobbyists who work on these bikes.

A description of what you did may shed some light on the effectiveness of the job you did on the carb units.
 

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Discussion Starter #5
You were spot on with the parts, the new jets had a different amount of holes from the old and the float needle was holding the float at 21mm, not 15.5 like spec. I put the old parts back in except for o rings, gaskets and the idle air screws. The idle is fine and there isn't any hesitation now except for the misfire which it had previously which is probably the plug wire on the right cylinder. Now the backfire is still there (also right cylinder), which was not there before the carb was pulled. When I went through the carb this time I thoroughly cleaned it.
 
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