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Discussion Starter #1
Bst38ss mikhuni's, any idea's why I would all of a sudden have fuel coming out the small main air jet on the filter side of the carb? It's only happening on #3. I've rechecked the diaphram and o-ring under the top, they both look seated properly.

120's in 1&4
122.5's in 2&3
14.7 (ish) floats
.5 pilot jets
Pilot screw out 2 to 2.5 turns.
Balanced the carbs this afternoon.

Falls flat on it's face at just a bit of throttle, clears up a bit if i back off, farts and kicks till it gets past 7 or 8k then runs like hell. Carbon fouls the plugs, but still pops on decell.
I had 112's and 115's, with the pods and header/pipe it was too lean. I knew it would be, but I installed new carb kits, including the needles and tubes, all the jets and wanted to start from square 1.
Went up to 116's and it was still too lean.
I've read where some are running 132's, 140's, how? I put anything bigger than 125's in it will hardly run.
I had previously driled out a small set of jets to what should be 120's, and it still fouls the plugs after a 10 or 15 minute ride, pops on decel, no power, and falls on its face.
Valves are all in spec, did a leakdown test-no problems there, compression is down a bit, but all 4 cyl's are within 5lbs.
I've been trying to follow the instructions as per the factory pro guidlines, but have been unsuccessfull so far. I just saw the gas coming from the main air jet this afternoon, and i know this is probably the problem, but I can't find the cause and what to do to repair it.
Any help?

tks
 

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there is known problem with the carbs on this model in that the needle jet tents to oval as a result of the needle vibrating in the opening. This causes the bike to be very rich just off idle until mid-throttle when the main opens up. The fix for this is to replace all needle jets and the jet needle too.
 

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Discussion Starter #3
Did that. Bought some Keyster kits #KS-0559. They come with almost everything. I took the carbs off tonight so I could make sure the diaphragms were in place properly, double checked the float heights, etc. Nothing seems out of place, the choke plungers retract as they should, needles are seated in the slides.....
I thought it best to start with a stock setup and go from there, but it seems like I've had more fuel delivery problems since the new kits than before. I never know when I hit the button if I'm gonna get Dr. Jekyll of Mr. Hyde, it either runs great or a temperamental piece of crap.
 
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