Carbs will not come clean!

When I first got the bike in March of last year, the carbs needed cleaning. I sprayed carb cleaner in the openings and blew um out with compressed air. The bike would not start w/o starting fluid. I took them app apart and broke the rack. Total break down of each carb and let them soak 24 hrs in partstore gallon of carb/parts cleaner. Blew out all passages with compressed air. Assemble with new shaft seals and rebuild kits. Bike does not start cold without starting fluid. Drive bike for 1000 miles using Shell 93 octane and a few cans of seafoam along the way. Runs nice but no cold start. Get Lens drill bit for the fuel bowls. Drill does make the opening bigger. Flush with carb spray and blow out with air. Still no cold start and now the plugs are black after a 10 minute ride. Take carbs off and soak in parts cleaner for a month. Blow out with air. Im ready to put them together when I read about the Harbour Freight ultrasonic cleaner. I get it and use hot water, the machines built in heater and 20% Simple Green. The water is almost black after the 8 minutes is up. Change cleaning solution and go another 8 minutes. Just as dirty. Flush carb under faucet and blow out with compressed air. A few days later, I decide to run them in the ultrasonic cleaner for good luck. The water comes out filthy again, and again, and again..... They been it the clean for over 2 hours total and the tank is still dirty today. What the HECK!!!

 

http://s89.photobucket.com/albums/k230/ ... IM0662.flv
http://s89.photobucket.com/albums/k230/ ... IM0662.flv
http://s89.photobucket.com/albums/k230/ ... IM0662.flv
http://s89.photobucket.com/albums/k230/ ... IM0662.flv

 

Have you checked your enrichment plungers are in correctly?
Black plugs = rich, so you are getting TOO MUCH GAS.

Hard to do with dirty carbs if I do say so myself. Sounds to me like the sonic cleaner is turning black more from a chemical reaction, but I have no idea. I can't see them being dirty enough to turn it that black, that many times.

Are you mixture screws in place properly?
Enrichment plungers in correctly?
Floats set correctly?

Someone will probably correct me, but 'dirty' carbs I can't see making your plugs black.
Are the plugs WET black, or dry black? Wet = oil leak via rings or valve train.

 

I had it running great with the mixture screws at 4.25, 3.5, 4, 4. I used Chacals starter jet drill bit and was able to feel it made the holes bigger. I guess I was able to tune the engine to run smoothly with the starter jets partially blocked meaning that all that time in the parts cleaner didn't do the job. Now with the ultrasonic cleaner I see bubbles come out from the carb and form little grey clouds and you can't see the bottom of the tank anymore. I threw my glasses in there with just water and saw the grey clouds forming from the hinge and nose pieces. Same thing with my watch. I believe there's still crud in the carb.

 

Hmm...

Well - first tidbit I got for you on the starter jet...

Don't FEEL for clean. Look for clean.

Firstly, shave a carb cleaner straw to a clean point, so it fits snug into the hole on the inside of the bowl.

Hold it tight, blast away. Keep away from your eyes!!!

After that, blow out with air - then take a strong penlight or keychain flashlight, preferably LED... hold it straight over the hole in the bowl, and look deep down into the starter jet hole where the drop down tube goes in. You should see a very clear white dot at the base.