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Discussion Starter #1
I've noticed reading these threads that a few of you guys have complained about low rpm engine stutter. I had exactly the same prob and took ages to eventually work out what my prob was. My answer, and I can guarentee most of your problems, stem from worn emulsion tubes. To check this out remove the carbs, then remove the emulsion tubes from each carb and check the hole that the needle moves up and down in. If it is worn AT ALL, thats your problem. As you open the throttle, because the hole has been opened out by the needle over time, it lets too much fuel into the engine air flow and 'stalls' the engine through over fuelling. The wear can be very hard to see, I suggest you use a magnifying glass. If you are in any doubt, change them. Factory Pro have some excellent info on the subject, with photos, on their web site. Also, as you have the carbs apart check the area of the needle that travels through the emulsion tube. Mine were worn and I replaced them with FP items which are less prone to wear.

Steve S
 

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Discussion Starter #3
Originally posted by resonantfreq:
do you think this would have anything to do with me stalling when the bike gets hot?
<font size="2" face="Verdana, Arial">Yes mate, it certainly could, especially if your bike has a few thou miles on the bores. My bike was fine when cold, because the extra fueling just acted as though the choke was on. However when hot the extra fueling 'over fuels' the engine and stalls it. If, when your engine is hot, and it idles OK, but stalls as you slowly open the throttle (especially when pulling away, with the engine under load), then I would definitely check your emulsion tubes / needles for wear.
Hope you sort it out. Steve S
 

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Can you buy new emulsion tubes, if so where? I didn't think that mine were removable, actually, now that I think about it. Are the emulsion tubes the little brass spacers that go below the screw on the main Jets. I think I know what your talking about now, correct me if I'm wrong. Also, I'm not sure if my carburetors have the stock needles or an aftermarket. Do the stock needles have adjustments at the top of the needle. Mine have adjustments. If you can though. Let me know where to get those. Also do you know how high the floats are supposed to be. If I tear it all apart I want to check the height. Could that be the cause of it. Sorry this is a lot of questions. I would just like to get this all worked out. Thanks.
 

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Originally posted by pacman-20:
Can you buy new emulsion tubes, if so where? I didn't think that mine were removable, actually, now that I think about it. Are the emulsion tubes the little brass spacers that go below the screw on the main Jets. I think I know what your talking about now, correct me if I'm wrong. Also, I'm not sure if my carburetors have the stock needles or an aftermarket. Do the stock needles have adjustments at the top of the needle. Mine have adjustments. If you can though. Let me know where to get those. Also do you know how high the floats are supposed to be. If I tear it all apart I want to check the height. Could that be the cause of it. Sorry this is a lot of questions. I would just like to get this all worked out. Thanks.
<font size="2" face="Verdana, Arial">First off, yes the emulsion tubes are replaceable, they are pressed in there pretty tight though... I used an "orange stick" ...one of those things that you push cuticles back with... to shove mine out with and seat the new ones. Ron Ayers can get you the OEM Suzuki emulsion tubes for way less money than the Factory Pro ones, which happen to be made of the same material (brass). I dunno `bout the `88, but on the `89 1100, there is no spacer underneath the main jets. Also, on the float-height... on the `89 1100 36mm carbs, it's 14.5mm +/- .5mm ... I have mine set to 15mm. You can change the float-height a *little* bit from the factory specs if it helps with tuning, but don't stray too far from there.

Hope that helps.
 

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Discussion Starter #6
hey pac, yes you can buy emulsion tubes, but they come with different diameter internal dimensions for different models, so if you buy a set , check that your needles are a snug fit into them before fitment. Before you remove your emulsion tubes, remove the top of your carbs and the sliders c/w the needles, otherwise the needles and sliders will get in the way. Remove the main jets, which actually screw into the bottom of the emulsion tubes, and the press out the tubes through and into the venturii. There is a ceramic cage( in the carb ventuii) that the tubes must also be pushed through. it is a very tight fit so be careful. When refitting be careful to orientate the tubes properly before pushing them home. The botton ends (which the main jets screw into) have a flat machined onto them which must mate correctly with the carb body. This is what will stop the tube rotating as the main jet is screwed into it.
As for float heights, well the floats are held into the carb bodies by the float bowl, which obviously has to be fitted to ensure the the floats are correctly positioned - catch 22. I've made a special tool that fits around the float and bolts onto the carb body so that the floats are held in the correct position before I adjust them. this has the added advantage of holding the float assembly tightly in place while you're working on them.
Hope all this helps, I can't remember the exact float bowl heights off hand, but again, buy a manual, it's worth it's weight in gold me old mate.

Both stock or replacement needles will have adjustment on them in the form of grooves (usually 4)and circlips. Height adjustment of the needles corresponds to which ever groove the circlip is positioned in. If you alter the groove position, you will alter your fuelling too. Best left to the experts. As I've said before, once you've finished tweeking your carbs, get them set up on a dyno.

Good luck, Steve S

[ 05-26-2002, 02:53 PM: Message edited by: TorF3 ]
 

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Thanks a bunch Steve, I have allready got my manual on order, it should be in this Thursday. I think I'll wait to tear everything apart again until I get that manual, that way I can do it right the first time instead of 3 times later like usual. If you think of anything else that I might need for this process, let me know. I really appreciate your advice. Thanks.
 

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Originally posted by FastCat:
</font><blockquote><font size="1" face="Verdana, Arial">quote:</font><hr /><font size="2" face="Verdana, Arial">Originally posted by pacman-20:
Can you buy new emulsion tubes, if so where? I didn't think that mine were removable, actually, now that I think about it. Are the emulsion tubes the little brass spacers that go below the screw on the main Jets. I think I know what your talking about now, correct me if I'm wrong. Also, I'm not sure if my carburetors have the stock needles or an aftermarket. Do the stock needles have adjustments at the top of the needle. Mine have adjustments. If you can though. Let me know where to get those. Also do you know how high the floats are supposed to be. If I tear it all apart I want to check the height. Could that be the cause of it. Sorry this is a lot of questions. I would just like to get this all worked out. Thanks.
<font size="2" face="Verdana, Arial">First off, yes the emulsion tubes are replaceable, they are pressed in there pretty tight though... I used an "orange stick" ...one of those things that you push cuticles back with... to shove mine out with and seat the new ones. Ron Ayers can get you the OEM Suzuki emulsion tubes for way less money than the Factory Pro ones, which happen to be made of the same material (brass). I dunno `bout the `88, but on the `89 1100, there is no spacer underneath the main jets. Also, on the float-height... on the `89 1100 36mm carbs, it's 14.5mm +/- .5mm ... I have mine set to 15mm. You can change the float-height a *little* bit from the factory specs if it helps with tuning, but don't stray too far from there.

Hope that helps.
</font><hr /></blockquote><font size="2" face="Verdana, Arial">FastCat,

How do you go about adjusting the float height on the little plastic floats within the float bowls???? Is it an easy task???? OR should I let a certified Suzuki mechanic do it????

Thanks,

JDB1371
 

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Originally posted by J.D.:
FastCat,

How do you go about adjusting the float height on the little plastic floats within the float bowls???? Is it an easy task???? OR should I let a certified Suzuki mechanic do it????

Thanks,

JDB1371
[/QB]
<font size="2" face="Verdana, Arial">There's no way I'd pay shop rate labor for someone to do this for me... well, if I won the lottery maybe... I enjoy tinkering with this stuff, although I realize that not everyone does. If your time is valuable to you and you have better things to do than play around with shiny bits of brass, aluminum and plastic all day, then you may wanna consider having a mechanic do it for you. If you *like* toying with mechanical things, then it's simple as can be. It is tedious, and it takes a lot of patience - that's all. The way you adjust the height is to simply bend the metal tab on the float assy. until the height of the floats is where you want them. the plastic frame that holds the floats must be held in place while you're carefully getting accurate measurements of the height where the needle hits the seat... it's not rocket science, just potentially frustrating. I made up a gage out of 1/8" sheet aluminum that has a cut-out in it at exactly 15mm. I used that and just kept making small adjustments to the tab `til I could see the needle hit the seat at exactly 15mm, and not go in any further when I pushed the bowls past 15mm. Do *not* bend that tab much or you run the risk of breaking them. You're measuring the distance from the carb body to the bottom of the float, so higher=leaner, and lower=richer. I'm told that the *most* accurate way to do this is to actually measure the fuel-level in the bowls with the carbs fully assembled on the bike... but that's *way* more time-consuming and tedious than I have patience for.
 

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Well, I've got my manual and ran into a few more problems. I've got my float heights good, and I've went through my carburetors I sware at least 30 times. If anybody has questions on how the carbs are dissasembled. I am the man to ask. But anyways. After a lot of trial and error I have finally located my problem. 2 of my float needles are bad, for some reason. on those two needles which ever carb I put them in, that cylinder won't fire. I'm guessing that it's making them really rich. So I'm going to buy a set of those, does anybody know a good place to get some from. Also, is there any way to repair mine, besides buying new ones that way I wouldn't have to wait. They look good, and the little thing that goes up and down on the top on both works great. There just malfunctioning for some reason. Also one last question. I know where it says in the book not to mess with the idle mixture adjustment screw. I bought these carbs used and I believe that they got messed with, does anyone know how to adjust them. There supposed to be factory set, and then not messed with. But there's got to be a way to adjust them. If anybody knows I'd appreciate your knowledge. Thanks in advance.
 

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Ron Ayers Motorsports is the *best* source I have found for OEM Suzuki parts. Give Chip a call at 1-800-888-3084; he can hook you up.

On the idle screws, the way I did it was to *gently* close them as far as they go, then back each one out 2 1/2 turns then install on the bike. Once you get the bike warmed up *completely* and have your carbs synched, just blip the throttle and pay attention to how it comes back to idle. If it blips up a few K and comes back slowly, they're too lean and you need to back them out more... go in 1/2 turn increments, and wear leather gloves to keep from burning your hands. If you blip the throttle and it goes up a few K and then drops slightly below the idle speed and then comes back up, then they are too rich and you need to turn them in. keep playing around with it and you'll find the place that works best. On mine, 2 1/2 turns ended up being the best setting. Be careful with backing them out too far... there's a spring in there that has to have tension on it or the screws will vibrate loose all on their own. If you have to set them more than 3 turns out or so, you'd be better off to go up a size on your pilot fuel jet and then re-do the idle screw adjustment.

Let us know how it works out!
 

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Discussion Starter #12
Pacman, all the above advice is good. But the best carbs in the world will run crap if not set up properly, and the ONLY 100% way to ensure carbs are properly adjusted is to have your bike dyno'd, and the carbs adjusted if necessary. When you think your set up is pretty close, take it for a dyno run. This will tell you every thing from correct jet sizes to float bowl height and needle set up.
Just make sure who ever you get to do it comes recommended.
Good luck, let us know how it goes.

Steve.

BTW float needles are not repairable, change all 4, if 2 have gone awol the other 2 won't be far behind. If they aren't cutting off fuel flow when the float rises then yes, the carb will flood and cause misfires.

[ 06-07-2002, 02:27 AM: Message edited by: TorF3 ]
 
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