Re:carb cleaner (found on the internet)
I boiled mine in lemon juice a couple weeks ago. 15 minutes of boiling in lemon juice cleaned them as thoroughly as a set my buddy had ultrasonically cleaned. Infinitely better than any aerosol carb cleaner is going to do, and way more environmentally friendly than a carb dip. If you use straight lemon juice boil for about 15 minutes. If you cut the lemon juice with water increase boiling time proportionally. 50/50 water/lemon juice boil 30 minutes. You don't need to pull any of the rubber bits out of the carbs because the lemon juice won't hurt the rubber, nor will the short time boiling cause any heat related issues.
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Lemon Juice Carb Cleaning(Found on the internet)
If it was me, I'd pull the top covers off, pull the slides out, drop off the bottom bowls, remove pilots/mains. Then with the rest of the carbs still assembled boil them in some lemon juice. You'll need a big roaster pan, a little over a gallon of lemon juice (cooking supply stores), and an understanding wife/girlfriend cause the sh*ts gonna stink a little.
Boil them for about 15 minutes, then rinse them really well and blow them dry with compressed air (make sure all passages are clean). You'll be amazed at how clean they come in that short of a time.
I just did a set yesterday after hearing about it from a buddy who's used lemon juice on a couple dozen racks of carbs. After a couple of minutes at slow boil the lemon juice starts to foam up a little (careful not to boil over) and you can see all the sh*t just dissolving.
After boiling them for 15 minutes (might have to roll them around once to make sure you get the entire carbs) rinse them really well and blow them dry with compressed air. The carb bodies will be kinda chalky looking at this point. I used a toothbrush and PB blaster to put a little luster back into them and then put my internals back in.
I had pulled the bowls off, removed the floats, float needles and seats, jets, and air/pilot screws as well as the top covers and slides just to make sure no crap got itself wedged inside those passages.
After putting the carbs back together and bolting them up not only do they look great but the bikes running MUCH better with all the jet passages finally cleaned out.