pilot air screw

[Black Knight]

i'm needing a bit of info of a location on the pilot air screws . My carb's are mikuni 49400 F237 . here's what i've found so far ..the float bowl's have a spot where the screw's go but there isn't a screw found . can someone put some light on the location of these screw's ? .

83 gs1100gld ..

 

[Nessism]

Suzuki installed caps over the screws. Remove cap before removing screw.

 

[Mak]

do u know if they are the VM or BS carbs ? which guide are you using for the rebuild ?

for bs/cv you might have to drill thru the caps to get to those screws

 

[Black Knight]

the cap's have been drilled out and all carb's have been rebuilt and synced ...All i'm wanting to do it adjust the air screw where it'll run idle and not fall on it's face . my buddy told me i need to adjust these screws to where the idle just begin's to raise then lower then it's adjusted .

nessism...has the pic of what my carb's look like ...

 

[BassCliff]

Hi,

Your bike has Mikuni BS34SS carbs. You'll find lots of pictures in the Carb Cleanup Series. <clicky

Here's a sample...

And here's something I whipped up from the carb manual you can download from my little website...

EDIT: I see you are actually referring to the "Idle Mixture Screws" (sometimes mistakenly called "air screws") and not the air jets.

CLICK HERE for tips on the "highest idle" adjustment method.

Thank you for your indulgence,

BassCliff

 

[Nessism]

the cap's have been drilled out and all carb's have been rebuilt and synced ...All i'm wanting to do it adjust the air screw where it'll run idle and not fall on it's face . my buddy told me i need to adjust these screws to where the idle just begin's to raise then lower then it's adjusted .

nessism...has the pic of what my carb's look like ...

How can we help you?

 

[Steve]

Start by turning them in until they seat LIGHTLY, then back out three full 360-degree turns. Start the bike, let it warm up. NOW you can adjust them for proper mixture.

Your buddy's suggestion is close, but rather vague. At three turns out, the mixture is plenty rich to allow starting and probably will not raise any more. Slowly turn each screw in until you detect a slight drop in engine speed. Back that screw out about 1/8 turn, go to the next carb. When you are done, go back and do them again, just to be sure.

You may find that they end up about 2 to 2 1/2 turns out. Record their final settings (each carb may be different) for future reference.

.

 

[Black Knight]

that vacume adjustment screw is the sync screw ..FYI the buddy has a PHd in engineering and is attending MMI in AZ he just doesn't mess with metric bikes ..I've learned alot from here and from him but you have to be here in person to see the problem ....

Sorry to have brought the issue up ...

Thank you have a nice and wonderful weekend ...

 

[Steve]

i'm needing a bit of info of a location on the pilot air screws .

Just so your PhD friend does not trip you up on this, those are NOT "pilot air screws".

You don't have any "pilot air screws" on your bike.

Those are "idle mixture adjustment screws" and contol how much of a mixture is admitted to the cylinder. If you reference the picture that BassCliff posted, you can see that the pilot air jet and the pilot fuel jet produce a mixture that is admitted to the airstream in three places. Two are on either side of the closed throttle plate. The third location is controlled by the adjustment screw. Turning the screw OUT (counterclockwise) will richen the idle mixture, turning it IN (clockwise) will lean it.

.

 

[BassCliff]

Hi,

Well, I guess I just don't understand what your asking.

If you go through the Carb Cleanup Series you'll see every nook, cranny, screw, jet, O-ring, and plug, with all the proper names. If that and the links above don't answer your question (What was the question?) then feel free to put up some pictures so that we can see what you're looking at. Some of the guys here have been "messing" with these metric bikes for 30 years and know them like the back of their hand. Keep us informed.


Thank you for your indulgence,

BassCliff

P.S. I fixed the name of the "Idle Mixture Screw" in my little diagram.

 

[Nessism]

I'm with Cliff on this one; I don't understand the question.

 

[Ranger]

I'm with Cliff on this one; I don't understand the question.

I got from it, he simply needed the location of something he was not looking for when in fact he was looking for something else.

 

[Flyboy]

he simply needed the location of something he was not looking for when in fact he was looking for something else

HUH??????
Ok, that has done it, I'm in the same bin with Ed and Cliff now.

 

[Guest]

the cap's have been drilled out and all carb's have been rebuilt and synced ...All i'm wanting to do it adjust the air screw where it'll run idle and not fall on it's face . my buddy told me i need to adjust these screws to where the idle just begin's to raise then lower then it's adjusted .

nessism...has the pic of what my carb's look like ...

Maybe , whom ever drilled the plugs drilled to deep and drilled the screw heads so now his phd buddy can't see the screw heads so they are looking else where

 

[Black Knight]

It's pretty bad when i come in here to ask a simple question and throw in some back ground info about a friend of mine that is trying to help me out . When he put's in his .02 you all think he's stupid and that just rude plain and simple . It doesn't matter how much you know about a machine or how many yr's you've wrenched on 1 or 50 . Were all here to learn from each other and i have alot to learn myself .

We have decided to take it to his school and let a suzuki tech adjust the issues .

thank's for the help and i won't be asking any more ?'s .

Have a nice day

 

[Nessism]

It's pretty bad when i come in here to ask a simple question and throw in some back ground info about a friend of mine that is trying to help me out . When he put's in his .02 you all think he's stupid and that just rude plain and simple . It doesn't matter how much you know about a machine or how many yr's you've wrenched on 1 or 50 . Were all here to learn from each other and i have alot to learn myself .

We have decided to take it to his school and let a suzuki tech adjust the issues .

thank's for the help and i won't be asking any more ?'s .

Have a nice day

You still haven't explained what the problem is. How can we help you if you don't explain in clear terms what's wrong and/or what you want?

The only info we have that relates to a problem is you say something about the bike "falling on its face". You aren't trying to run the bike without the airbox are you?

Guessing sucks. If you provide some more info, and a photo or two like Cliff suggests, I'm confident we can help you without the expense of taking the bike to a mechanic.

 

[Flyboy]

Not too sure who is suposed to be being rude and nasty here, the way I see it;

Black Knight asked;

i'm needing a bit of info of a location on the pilot air screws

Ed replied;

Black Knight Replied;

All i'm wanting to do it adjust the air screw where it'll run idle and not fall on it's face . my buddy told me i need to adjust these screws to where the idle just begin's to raise then lower then it's adjusted .

So this would seem to be the second crux of the matter, and the actual request for info, after the mixture screws were/were not located.
I think at this point there is confusion around the terminology of the screws (air screws versus mixture screws)

Cliff corrects this and replies;

EDIT: I see you are actually referring to the "Idle Mixture Screws" (sometimes mistakenly called "air screws") and not the air jets.

Steve catches the pass perfectly and replies;

Start by turning them in until they seat LIGHTLY, then back out three full 360-degree turns. Start the bike, let it warm up. NOW you can adjust them for proper mixture.

Your buddy's suggestion is close, but rather vague. At three turns out, the mixture is plenty rich to allow starting and probably will not raise any more. Slowly turn each screw in until you detect a slight drop in engine speed. Back that screw out about 1/8 turn, go to the next carb. When you are done, go back and do them again, just to be sure.

You may find that they end up about 2 to 2 1/2 turns out. Record their final settings (each carb may be different) for future reference.

Seems there is still confusion as to the terminology of said screws, despite being corrected, it would appear the buddy is having none of it and begs to differ, insisting that the mixture screws control air/vacuum

Black Knight replies;

that vacume adjustment screw is the sync screw ..FYI the buddy has a PHd in engineering and is attending MMI in AZ he just doesn't mess with metric bikes ..I've learned alot from here and from him but you have to be here in person to see the problem ....

Yes, we are well aware that the vacuum adjustment screw is the sync screw, it would appear the buddy is still looking for the screw that controls the idle via air/vacuum metering, which as we know, and as Cliff has already explained.
Steve explains it a second time, and I must admit, I can now not see how there can be any confusion

Steve Replied;

Just so your PhD friend does not trip you up on this, those are NOT "pilot air screws".

You don't have any "pilot air screws" on your bike.

Those are "idle mixture adjustment screws" and contol how much of a mixture is admitted to the cylinder. If you reference the picture that BassCliff posted, you can see that the pilot air jet and the pilot fuel jet produce a mixture that is admitted to the airstream in three places. Two are on either side of the closed throttle plate. The third location is controlled by the adjustment screw. Turning the screw OUT (counterclockwise) will richen the idle mixture, turning it IN (clockwise) will lean it.

Then it seems Black Knight threw a wobbly when after having both his questions clearly and constructivly answered, and Ed, Steve and Cliff could not figure what further information he wanted, and just asked.

Sorry guys, seems to me the buddy with the PHD and MMI and all that Jazz does not believe that you PO shade tree mechanics know to much about the workings of a metric motorcycle, well not a GS anyway.

Why ask for information then argue with the answers? It is so uneccesary for a bit of miscommunication to leave a bad taste. I hate it.

 

[BassCliff]

Hi,

Ed is absolutely right. These bikes will "fall on their face" if you run stock jetting without the airbox installed. Perhaps if we had more accurate information the underlying issues would be obvious. I encourage you to take the time to utilize the resources here. This is absolutely THE place to learn about these bikes.

Thank you for your indulgence,

BassCliff

 

[Mak]

.....if you think YOU had it bad, try reading this thread after a six-pack on an empty stomach.... "I'm freakin' out maaaan!"...

 

[Roostabunny]

.....if you think YOU had it bad, try reading this thread after a six-pack on an empty stomach.... "I'm freakin' out maaaan!"...

Actually, I think you'll bring the thread full-circle when you try to get up from your computer and "fall on your face".

Edit: I may be underestimating your tolerance, but speaking for myself, (1 Six pack + Empty stomach)/One thread = faceplant