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Discussion Starter #1
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I've check the float height and it is the same on both carbs yet only this one weeps.
 

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Discussion Starter #2
Just spent some time verifying the float height and man was I off. I'll admit I never had a very good technique for checking even with a float height tool, however I may have it down now.
I found that if I rest the carburetor on the workbench with the float hanging, I could rock the carburetor back and could watch the float stop swinging as soon as it hit the valve. Then with the float height tool already resting on the opposite, when the float stopped swinging I would lower tool on the side closest to me and could clearly see if it hit or didn't and how much.
That should take care of the weeping. Now I've got to figure out where I'm at with the jetting. Kinda back to square one.
 

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If you have one of those cone shaped vacuum adapters and some clear hose you can remove the bowl drain screw with the petcock off, insert the vacuum adapter in the drain hole, hold the clear tube up and open the petcock. You will be able to see the level the fuel is at.
 

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Discussion Starter #4
Sounds interesting but I don't follow. I think my new "technique" is gonna work for me. I'm getting consistent readings now.
The question now is; where to go with the jetting?
Bike runs/ran well-ish. Plug chops show ever so slightly rich at idle, lean-ish (grey) everywhere else on a 90 degree day. Fuel screw was only 1/2 turn out. I've currently have a #38 pilot, #72 secondary, and #115 main installed. Bike started, idled, reved and generally performed well except for some flatness when having the throttle wide open and a bit of surging around 5k rpm. No popping except for when really hammering on it you'd get one little pop in between shifts.
 

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sounds like you went up 2 sizes on all jets...did you install a larger exhaust and air box to handle the extra fuel?

if not go back to your stock jets
 

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Discussion Starter #6
Exhaust is stock headers with some kinda aftermarket muffler. The one's with a bunch of little pipes at the ends. I think SCI sells them. Air box is stock with new filters. Bike has/had run lean since 1/4 over bore, Charlie's Place ignition and Dyna coils installed. Speaking with Charlie, he tells me "I have to jet the heck out of these with this set-up and haven't had much luck going over #40 on the pilot." And his advice on the fuel screw is "avoid the extremes."

Thanks for chiming in Outbie. Waiting on gaskets for the CL too so, my place is kind of a mess. Hoping to get the CB just right and try the same settings on the CL. (Carbs are tough to get off the CL thanks the the rad pipes)
 

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your idle mixture screw being at 1/2 turn says the opposite....

stock mixture setting starting point is 1.25 turns out...at 1/2 turn, it says your pilot is too rich.

Charlies place is good but I'd disagree with your statement from them above.

your modifications don't warrant that much extra fuel in my experience.
 

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Discussion Starter #8
I didn't think so either but I had what I thought was a lean condition due to jetting. I think my ability to adjust valves, timing, cam chain tension and carb sync has improved after much practice so my suspicion is that one or some of those adjustments was playing a roll. I'll head back to stock jetting and see what happens.
 

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if stock jetting appears too lean with your exhaust and filter combination I'd suspect an air leak around the carb boots or the felt around the throttle butterfly shaft or possibly in your exhaust

warm up the bike by riding for 10 min (if possible) then when idling spray WD40 or similar around the carb boots and butterfly shafts...if that has ANY effect on idle you have an air leak.

ignition timing (as confirmed with a strobe for both sides ensuring advance and return happen smoothly)
carb and throttle cable synch being spot on

valve adjustment being spot on.

all will have an effect on your symptoms.

are the floats undamaged and set properly?
did you replace all the rubber orings on the jets and plugs.

put the stock jets back in...by the way, it's not recommended to clean jets with wire...it tends to change the size of the jet making it larger.
 

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Discussion Starter #10
Carb intake boots are new. Always use new o-rings on the jets and new plugs. Floats are and set properly, now. I'll check the timing with a strobe when I get back together. Would love to replace the felts but they didn't look to bad and don't remember if I had looked for some. No cleaning with wire.
I'll get it back together tonight and keep ya posted.
Thanks.
 

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Carb intake boots are new. Always use new o-rings on the jets and new plugs. Floats are and set properly, now. I'll check the timing with a strobe when I get back together. Would love to replace the felts but they didn't look to bad and don't remember if I had looked for some. No cleaning with wire.
I'll get it back together tonight and keep ya posted.
Thanks.
if you soaked the carbs in berrymans or similar carb cleaner it tends to wash all the moly lube off the felts which allows them to leak air. don't replace them but do reoil them

when using the strobe be sure to tack the motor up to 5K rpms then roll off several times...you want to watch to see the timing lite evenly advance from idle to full advance and back again smoothly for both left and right cylinders. jumpy timing occures when advancer is worn.
 

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Discussion Starter #12 (Edited)
And...Floats are new, definitely have massive exhaust leaks where the muffler connection to the headers are. Was thinking about getting some of those step down collars from Dime City or the ones Common-Motor Collective.
 

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Ignition changes (Charlies Place, Coils, PLugs/Wires) will never affect mixture. Not sure why people think this. Float height affects mixture. The higher the level in the bowl, the richer the mixture. However, this causes smaller changes. So if you are slightly rich, a lower fuel level in the bowl (A larger number on the float height) will lean somewhat.

Since the factory pretty much had the mixtures right from the factory, a poor mixture (rich or lean) today means that something has a problem. Blocks carburetor passages, emulsifiers with blocked openings, air jets blocked or clogged, worn throttle shafts or shaft seals, leaking rubber manifolds- Loose, leaking gasket, cracked rubber and also diaphragms with pinholes or tears. If you have a predominately stock intake and exhaust system, then the original configuration will work perfectly if the carburetor is in a good state of cleanliness and adjustment.

Going to larger jets means there is another underlying issue you are compensating for. The rich idle condition shows you compensated by changing the idle mixture. Fixed right, the bike would run like a new bike. If it isn't you likely missed a problem.
 

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Discussion Starter #14
Thanks Mydlyfkyzis.
To clarify, a high number on the float height would cause a lean condition? How about an exhaust leak? The mufflers (aftermarket) have always fit poorly despite my best efforts to seal them up. I've ordered some kinda gasket from Common Motor Collective to see of they will work.

Thanks again.
 

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Discussion Starter #15
Back to the title of the thread. What causes that thingy to weep? I was thinking too much gas in the float bowl but my thinking was backward on that. If the float being high = lean (less fuel in the bowl) is what I had.
 

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That is the atmospheric vent for the carb. Splashing of the fuel would cause a weep. Are the rubber manifolds soft and pliable or hard as a rock. Hard rubber would allow more carb vibration/splashing....
 

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Discussion Starter #17
Update! Update! IT'S ALIVE! again.

The bike runs great! My six year old son and I rode to local Honda shop to return a set of ring compressors I borrowed for my CL reassembly. It was only 20 miles or so round trip and clearly didn't do any serious rippin' with my kid on the bike, but overall seems like with the help of this forum and especially Mydlyfkrsis and Outbie my CB is now sorted out.

Changes made included going back to stock jetting, adjusting the float height and making sure the felts were oiled. Also I really went off the deep end making sure I didn't have any exhaust leaks. I say off the deep end because I end up buying new mufflers which then required fabrication of some mounting brackets.

Time will tell if things hold together and I'll do some plug chops to get more data.

Thanks for everything on this one folks, I really appreciate it. canvas.png
 
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