@gggGary Not offended at all all advice is taken as a helping hand I'm glad you guys even contribute to people problems here and am grateful for any insight. I'll also try out the non hardening sealer pretty sure I have some permatex in my tool box let y'all know how it goes
 
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Permatex (I think?) makes a fuel resistant, non hardening gasket sealer... I had to use that on an intake mount that just wouldn't seal up with the typical gasket & bolt pressure. Was going to file the intakes on the head but figured I would give it a try first... I used a very light/thin coat on the mounting gasket, then any excess that squeezed out was removed from inside the intake before the carbs were put on. Let it set for about a day, and no more air leaks. It has held up extremely well, and removal of the sealer (after about 6 months) to work on the top end was super easy. Even made removing the gasket a pleasure as it came off in one piece and and nothing was stuck on the head.
I like this. The end result is the same and it's not touchy. When you have a thinnish flange with a bolt on both sides and a gasket, it tends to bow the flange away from the gasket in the middle. If you're wondering if the leak at the head gasket is real, block the carbs with a big piece of cardboard and spray away from the carbs so there's no other explanation other than a leak at the gasket. If it's there, again I would use a small bead of the same type of sealer on both sides. By far the easiest solution. You said you rebuilt it, so the gasket is new.
 
BUT. If the plugs look okay, not extremely lean or anything, I'd happily ride it as is till it got a lot worse. Sounds fine.
 
New mounts won't necessarily eliminate an intake leak. If Mr. Cavewrench went neolithic on the screws at some point, the holes can become extruded and prevent the mount from sealing. If you find raised edges, use a flat file (and some flat files aren't, check first!) with light strokes, followed by 320 paper, to level the surface.
If the thread is pulled out/extruded slightly, I also would recommend countersinking the thread hole slightly, maybe 0.5 to1 mm, to be 100% sure.
The oem XS intake rubbers require paper gaskets, and so do JBM, and possibly other aftermarket items as well. But the non-angled 40 mm ID intake rubbers I got from Allens Performance have an integrated o-ring seal. Much better IMHO.
 
I think that there is far too much concern voiced over using gasket cement to seal joints .;)

Lets face it nobody is going to be removing their inlet stubs every year are they !... removing hardened gasket cement and gaskets is a pita its true but its unlikely that most owners are ever likely to need to remove their inlet stubs again in the lifetime of their use of their bike and I for one would rather have a permanent air seal and suffer the rare hassle of needing to remove the stubs and gaskets.

So my recommendation is to use a liquid gasket cement like Threebond 1104 or Hondabond etc and apply to both sides of the inlet gasket to cylinder mating surfaces ...once that is done you can completely forget there being any possibility of an air leak there. It is designed to fill rough surfaces scratches dings etc.

Next I would check your slides . it sounds to me like the slide diaphragms are leaking which is causing bogging on throttle transition from idle . Do the slide drop test and you should see your slides dropping in around 15 seconds or more . Any less and you have a leak;)

What happens to your idle if you apply a small bit of choke ?
 
Time for the update

@peanut my diaphragms are solid did the check just to make sure and They drop pretty much exatcly at 15 seconds.Also when I turn the choke off my idle goes up. Shouldn't it be vice versa? My Idle should be goin down correct?

Besides that I put the permatec non hardening gasket on the intake manifold both sides of the gasket and also in the throttle shaft seal of the carbs it worked well.
Definatly no leak at the headgasket after that.

My plugs are slightly rich which is good. My only thing I notice is I now have an aggressive backfire on the right side exhaust at times. And when I turn the mix screw on that side it doesn't make a crazy difference as compared to the left side. Should I be concerned about that as well as the choke issue? Or y'all think I should just ride it out and see what happens
 
good news about the inlets .................not so sure about putting permatec in the throttle shaft seals but as a diagnostic it shouldn't harm ...I usually use Vasoline to test for small air leaks on carbs
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Are you certain that you have the rubber lips of the throttle shaft seals facing OUT away from the carbs ? The suction from the engine vacuum should pull the seal lips in against the throttle shafts creating the seal.I cannot see how new seals could have significant leaks unless they were put in back to front .

Its difficult to know what to suggest next as we have so little information.

The spark plugs will only give you meaningful information when the engine has been run hard for many miles and thoroughly warmed up and then you need to think about what throttle position you are checking the mixture for .

leaving aside potential electrical and ignition issues I would concentrate on your idle and find out why one cylinder is backfiring and not responding to the idle mixture screw . Backfiring is generally due to a lean mixture hence the lack of response to the mixture screw perhaps
Check that the idle air jet is clean , at idle you are concerned with the idle jet , idle air jet ,mixture screw , slide, and the tiny idle fuel and air orifices in the venturi roof above the butterflys and don't forget to check that the choke valves are shutting off properly
 
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My throttle shaft seals are in the correct position the lips are facing away from the carb. I ordered another 76 right side carb body see if thatll solve my lean backfiring issue from what I assume is at the throttle shaft seal . I'll clean out the jets and orifices again see if that leads to any solution. I'm so close just want it to be done properly so I can start riding and working on separate issues like redoing wiring and fork seal all that jumbo. But thanks everyone when I have further results I'll let you know how it goes.
 
it doesn't take much of an air leak to throw your idle mixture out .

A useful way to temporarily eliminate any potential air leaks for testing purposes is to apply some Vasoline around the carbs anywhere there is a joint or blanking screw

I found a tiny leak on one of the choke bodies on my BS38s once.I skimmed the choke bodies flat on some wet n dry and then applied a smear of Threebond in order to cure the leaks.

Using an accelerant anywhere near a set of carbs will find air leaks in all sorts of obscure places not necessarily near where you point the spray.
I would replace the choke body gaskets and check that all blanking screws into the body have washers and are air tight too.
 
when I turn the choke off my idle goes up. Shouldn't it be vice versa? My Idle should be goin down correct?

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that would suggest that your idle mixture is too lean....ie an air leak ... at least on one if not both of your carbs.
What pilot jets do you have fitted and how far out do you have your mixture screws ?

I also forgot to ask is there any float on your throttle shafts ? ie side to side movement . ?

 
I'll try the vasoline method seems like a proper diag technique. I have went back to stock jets and mains seeing as I was running pretty rich with the step up jets. My mix screw on the left side is turned 1.5 turns and on the right about half a turn to reduce the backfire I was having. I'll also get some choke body gaskets. I've seen people have burs on theirs and I checked clean as a whistle applied a small amount of non hardening gasket prior as well help any seal but will look into again.

My throttle shafts had no up and down play I didn't check side to side . I didn't know to check for that but thanks for that video I've never seen it before and very informative I'll use my feeler gauges and caliper to check it out just like the the fella in the video.
 
Also the bore for my throttle shaft doesn't look out of round either it's a solid circle not sure if it would be visually noticeable or not jut putting that out there
 
that 'fella' in the video is me lol :)

Just use feeler guages as in the video until the shaft doesn't turn without binding and that is the total float .
If its more than 5 thou you'll need to reduce it by adding a shim washer as per the vid.

I am very doubtful that the throttle shafts are leaking to any significant extent. No matter how worn the shafts and bushes are the new seals should virtually eliminate any air leaks .

I suspect that something else is causing this issue.

Tell us exactly what jets and needles you have fitted so we can advise better. When you changed them you should have noticed some sort of difference .... we need that information because we cannot see and hear the engine running.
 
O nice hahaa proper video with good instruction thanks for making that.

At the moment I have stock everything in reference to jets and needles 122.5 mains and 25 pilot the needles jets are also stock z-8 and the 4m needle.

I didn't notice any real difference when I swapped the jets besides from the harsh backfiring from the right side.

The clearance I have on my carb the total float is .022thousantbs of an inch or ..559 mm so I would need a .017 shim correct? From what I understand the clearance should be no more than .005. What I find odd is the side that has no leak also has a .022 of an inch clearance. I can get a shim for the other side regardless see how it plays out

Was gonna test my choke gaskets with the vaseline method today but the holding clamp for one of the carb broke and was too late for store to be open ill get to it tomo and try it out just wanted to provide an update and let you know i see the help bieng given I'm
Not taking it for granted just have a lot goin on.
 
Even with that amount of float on the throttle shafts that would not be the cause of back firing or even particularly uneven idling
As I said previously the cause for those symptoms lies elsewhere .

If you want to prove it smear some vasoline around the throttle shaft ends and you'll see it makes no difference .;)

The backfiring .........is that at idle ?or is that on deceleration ?
The essential thing to keep in mind when tuning or trouble shooting carbs is that you need to split the job into seperate parts of the throttle range because each part of your throttle uses different components . ie ....Idle , 1/4.... 1/2... WOT and throttle transition from idle .

I always recommend concentrating on the idle first and get that correct because the idle mixture contributes all the way through the rev range except wide open throttle (WOT ) but more importantly your idle mixture protects your engine from over heating on deceleration.

Forget the jet needles and needle jets and main jets for the moment and dial in your Pilot jets.
 
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