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Having trouble with the idle circuit on carbs 1 and 3 being too rich. Even with the mixture screws turned all the way in, still reading rich with a colortune. Where else can fuel get into the idle-low end mix besides the idle circuit?
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80 XS11 "Bellatrix"- MAC 4-1, ZRX1200 carbs, Dynatek Coils, Raptor CCT -
The float level may be too high.Greg
Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”
― Albert Einstein
80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.
The list changes.
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Did you recently rebuild your carbs? Did you dismantle the needle valves? Did you make sure they are installed in the correct order of components? If not, it can cause the circuit to run very rich at idle. DAMHIK
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81 XS1100 Special - Humpty Dumpty
80 XS1100 Special - Project Resurrection
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93 GSX600F
80 XS1100 Special - Ruby
81 XS1100 Special
81 CB750 C
80 CB750 C
78 XS750Comment
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These are the early model carbs. The problem existed before rebuilding them. I just rebuilt them last night and the problem persists. All floats are set to 1" (or roughly 25.7mm ). All jets, needle valves, gaskets and needles are brand new.
42.5 pilots, 137.5 mains, 180 pilot air jets
It is important to note that the #3 carb had a pilot jet that got stuck, had a screw extractor break off in it and was redrilled and tapped. I can understand if that one is always going to run rich as I'm pretty sure there is no recovering from that. But why is #1 still doing it? It's got plenty of spark to burn the fuel as I'm running Dyna coils and wires. Carbs have been thoroughly cleaned with cleaner and compressed air.
With the mixture screw seated how else can fuel get into the idle mix?80 XS11 "Bellatrix"- MAC 4-1, ZRX1200 carbs, Dynatek Coils, Raptor CCTComment
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I dunno if this helps but I'm using a colortune to try and dial in the idle mix. On the #1 cylinder, the mixture screw is seated and it still is showing through the colortune as yellow. I can't even get it close to blue unless I fully remove the air pilot jet. Same thing for the #3 cylinder. Cylinders 2 and 4 have no tuning problems.
My rebuild kits also came with mixture screws. Which I thought might have been the problem before since all my mixture screws were jacked up.80 XS11 "Bellatrix"- MAC 4-1, ZRX1200 carbs, Dynatek Coils, Raptor CCTComment
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Are you sure there aren't any broken idle mixture screw tips still stuck in the carbs? You say the old screws were jacked. Were the tips blunted?Greg
Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.”
― Albert Einstein
80 SG Ol' Okie;79 engine & carbs w/pods, 45 pilots, 140 mains, Custom Mac 4 into 2 exhaust, ACCT,XS850 final drive,110/90/19 front tire,TKat fork brace, XS750 140 MPH speedometer, Vetter IV fairing, aftermarket hard bags and trunk, LG high back seat, XJ rear shocks.
The list changes.Comment
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Yes, quite certain. I checked them all last night while I was doing the rebuild. There was one that was stuck, but I unstuck it.80 XS11 "Bellatrix"- MAC 4-1, ZRX1200 carbs, Dynatek Coils, Raptor CCTComment
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