Does fuel/air adjust screw on 82 GS850 control air or fuel flow??

[Guest]

Guys,

I want to be clear on what I am adjusting. I have found some contradictory info in the threads for the adjustment ...if I back the screw out (counterclockwise), am I increasing the fuel flow (making it richer?) or am I increasing the airflow and making it leaner???

Please help me settle this.

Thanks

[terrylee]

Counter clock wise makes it richer, clock wise leaner. At least on your CV carbs, Vm carbs are opposite on air screw and also have separate fuel screw, just fyi. terrylee

[Gary_t200]

I checked the BS32 carb manual on bikecliff site and it shows that an air/fuel "mixture" runs through the pilot port into the throat...there is both air AND fuel entrained in the pilot flow.

So it wasn't clear to me if the "net" effect of increasing the flow through the fuel/air port was to make it leaner overall or richer overall.

So if I screw out (counterclockwise), the net effect is to add more fuel, making it richer? I guess the increased air flow rate sucks in more fuel?

[JTGS850GL]

Yes, adds fuel.

[chuck hahn]

I doesnt just add fuel..it adds a premixed MIXTURE of fuel and air that was mixed down in the bowls.

[Steve]

Yes, the screw contols a mixture to the low-speed operation. Turning it out (counter-clockwise) will richen the overall mixture, turning it in will lean it.

The factory set them on the lean side to meet with EPA regulations, which caused the bikes to run poorly and took forever to warm up enough to ride. Most of us have found that a setting of 2 to 2 1/2 turns out works quite well, but we start at three turns, to ensure a nicely-rich starting point, then lean it out to where it runs best after the bike is warm.

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[Gary_t200]

Good...I got it now...I opened to 3.5 turns, but I think I should have started by re-oiling my air filter. Last I oiled was last summer and it ran awesome. Then this spring it was running lean and surging a bit...dont know why I didnt go first to the sir filter.

I will oil tonight and then take it for a spin. Bet that fixes me and allows me to screw the pilot back in a bit.

Thanks guys

[Steve]

What filter do you have that requires oiling?

No matter, it does not take much oil.

If you put too much oil on the filter, you will choke off the air flow

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[mrbill5491]

Good...I got it now...I opened to 3.5 turns, but I think I should have started by re-oiling my air filter. Last I oiled was last summer and it ran awesome. Then this spring it was running lean and surging a bit...dont know why I didnt go first to the sir filter.

I will oil tonight and then take it for a spin. Bet that fixes me and allows me to screw the pilot back in a bit.

Thanks guys

Ummm, did you clean the filter first?

[Gary_t200]

Yes. Turns out it was pretty dry so I loaded it up with oil, squeezed it out and now my problem is solved. I should have done the filter right away instead of messing with pilot screws. lesson learned.

[jprice90]

At 2 1/2 turns out from slightly seated, i go Some backfires, still trying to get it running correctly but.the backfires came after tuning the air screws. Should i turn them back in some?

[Steve]

Personally, I would turn them OUT about 1/4 turn.

It amuses me constantly that OLD threads are being resurrected.

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[helmutholderbenz]

Yes, the screw contols a mixture to the low-speed operation. Turning it out (counter-clockwise) will richen the overall mixture, turning it in will lean it.

The factory set them on the lean side to meet with EPA regulations, which caused the bikes to run poorly and took forever to warm up enough to ride. Most of us have found that a setting of 2 to 2 1/2 turns out works quite well, but we start at three turns, to ensure a nicely-rich starting point, then lean it out to where it runs best after the bike is warm.

.

Thanks for this!

[jprice90]

ok, thanks Steve. It's ok, it's not that old sir

[Steve]

ok, thanks Steve. It's ok, it's not that old sir

Just two weeks shy of a full year.

The thread might not be "that" old, but I AM.

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