#3 not firing, RPM ghosts

[audijunky]

Well I have adjusted the butterflies on the carbs so that it doesnt idle at 5000 any more. Started the bike was idling at about 800. after about 45 seconds, idle started to increase on its own. SO when it reached about 3000 I actually pushed down with a on #4's idle adjust screw, which in turn lowered the RPMs back to around 1000. Some how the carbs are just opening themselves up. If I take pressure(not a lot) off of the screw RPMS increase gradually and just keep on climbing. This maybe related but if I give it gas the RPMs stay where I increased it to when I let go of the throttle. The springs that close the butterflies in the carbs still have plenty of pressure(I think) pretty stiff, hard to hold open by hand. Also #3 is not firing ,Header pipe not as hot as the rest. I have spark, and the boot between the carb and head had fuel in it when I removed the carbs, so I am stumped. The spark plug was black and smelled of fuel. Not like crusty black more liquid black( Icould wipe it off with my finger)Ordered a Compression tester and should be getting it soon. Ill post readings asap. Any body got any Ideas?

[DiverRay]

Audijunky,
#3 is flooding. Check the floats for holes, and check the needle and seats. Did you replace the "O" ring if it's a newer model?
You should NEVER have raw fuel in the carb boots.
After you have the flooding fixed, you can work on the idle speed. The "bread tie" sync method will give you a high idle, so you'll have to turn it down as soon as the bike starts. You then need to sync the carbs per the book, turning down the idle every now and then as you do.
Ray

[audijunky]

Well I just put brand new floats in, How do I check the needle and seats? Is this the needle that is attached to the diaphram assembly? just cleaned every part on all four carbs so beside gunk I don't know what to look for. All four of the boots between the carbs and head had fuel in them. Not tons but the boot was wet on the inside and had a small puddle around the bottom of the butterfly.

[DiverRay]

What year are the carbs/bike? the '80 and up carbs have an "O" ring seal around the seat. The needle and seat is what the floats operate to shut off and open the gas flow. The early machines have the seat screwed in to the carb body, and the later one has the seat held in place with a screw and coller assembly. The later model uses an "O" ring that fits around the seat, and is inside the carb body when everything is together. IF the "O" ring is leaking, the gas will ALWAYS be flowing into the carb.
Ray

[audijunky]

I have a 79 xs standard, So I guess I dont have an O ring. Stock Carb, Mikuni BS34-II. Yesterday I pulled the carbs and put a new needle and main jet in #3. I also pulled the spark plugs to put some oil in the cylinders, noticed all plugs looked like #3. knida black and sooty, but not where they spark. Dont know if that means anything but I appreciate the help. I am gonna start her tonight and see if the changes help.

[DiverRay]

Did you replace the needles and seats when you cleaned the carbs? I would also check the floats, and make sure they are not dragging on the inside of the carb. If one of the float supports is a little bent, it can cause the float to drag on the float bowl, and stick.
And make sure the fuel is connected to the BOTTOM "T", and the top "T" is open or connected to the airbow. Top "T" is the float vent on theose carbs.
Ray

[audijunky]

When I cleaned the carbs I did not replace the seats and needle just cleaned them. I noticed when I put the new needle in #3 that the new one was longer than the original. about 2 or 3 miilimeters. not sure if it means anything but Ill find out. The new floats are moving freely in the bowls. When I reassembled them I did the flip test individually to make sure they would float. And I do have the fuel/ air lines hooked up correctly. So I will let you know what I find out tonight. Thanks DiverRay

[pggg]

Audi if you mean the needles as in emulsion tube needles, the ones on the slides, they're stamped, 5GZ6 is usual on 78-79's. All 4 should be the same. If there's one 2-3mm longer, thats a leaner needle if set on the same notch as the other 3. Possibly a 51Z7 or a 5Z1. Ditto for the stubby float needles in the fuel bowl. All 4 have gotta be the same size.