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Suspected vacuum leak with stock Mikuni carb

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Hi everyone, I have a mostly stock drz with a yoshimura tri oval pipe with the 3x3 mod.

My problem begins when I start riding, your typical vacuum air leak idle issue.  It idles quite high every time you stop and pull in the clutch.

Is there a quick fix for the mikuni carb to fix the air leak?  Is there adhesive you can add to the vacuum dome rubber near the top of the carb?  I'm going to take this carb out and check the jets and spray carbclean in it anyways, and figured I'd look into this as well.  I will check all the boots when I remove it, but just want to know of any tips to fix internal carb vacuum leaks.

Again, I am very aware you can spray quick start around the boots to check if that is the leak, just want to know if there are any other mikuni fixes, like there are for the fcr 39.

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Hi everyone, I have a mostly stock drz with a yoshimura tri oval pipe with the 3x3 mod.
My problem begins when I start riding, your typical vacuum air leak idle issue.  It idles quite high every time you stop and pull in the clutch.
Is there a quick fix for the mikuni carb to fix the air leak?  Is there adhesive you can add to the vacuum dome rubber near the top of the carb?  I'm going to take this carb out and check the jets and spray carbclean in it anyways, and figured I'd look into this as well.  I will check all the boots when I remove it, but just want to know of any tips to fix internal carb vacuum leaks.
Again, I am very aware you can spray quick start around the boots to check if that is the leak, just want to know if there are any other mikuni fixes, like there are for the fcr 39.

That's not necessarily a vacuum leak. It's referred to as a hanging idle and can be from a lean pilot circuit or a variety of other causes. On the stock bsr carb, I find that a typical cause of hanging idle is that the idle is set too high and then the mixture is compensating for the high idle setting to achieve a lower idle speed. If your jetting is stock, I would start with a JD jetting kit and I bet it will be solved. If your bike is already jetted, I would turn the idle speed down til it almost dies and then lean the mixture til it comes back up a bit.

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