Running rich

[PaulD]

Just noticed on the chart it says the pilot screw is preset 2 1/2?
Is this 2 1/2 turns out and as mine are all set 3 1/2 turns from fully home would this make it run rich?
I’m more used to two strokes and this would only alter the off idle mixture and turning it an extra turn would lean it off so I’m a bit unsure with this.
Maybe the P.O. has tried to lean it off this way?

[Kryten]

According to the Suzuki manual above: Slow running is achieved by air being drawn into the carb through the pilot air jet. It then travels through internal passage.

It draws fuel from the float bowl via the main jet.

Then the mixture is drawn towards the pilot screw, but part of the flow is fed into the carb adjacent the butterfly, this gives a baseline fueling for this stage.

The pilot screw then meters the remainder to optimise the fueling at this stage.

Unscrewing the pilot screw allows more fuel/air mix in. Screwing it in leans it off. So you are right that maybe in the past they have been set that way which would make it rich.

As for figures anywhere between 2 to 3 1/2 turns out from closed seem to be acceptable depending on the air filters, exhaust and general tune of the engine.

Best thing to do is set them with the engine running. There is some where on one of the web forums a rule of thumb about how the engine behaves having blipped the throttle being an indicator of how close the pilot screws are to being right for that engine. But I can't remember where.

[Kryten]

From the GSresources over the seas:

https://www.thegsresources.com/_forum/s ... n-CV-Carbs

Posts 2 & 3 from the Koolaid Kid

[Uncle Bob]

Just noticed on the chart it says the pilot screw is preset 2 1/2?
Is this 2 1/2 turns out and as mine are all set 3 1/2 turns from fully home would this make it run rich?
I’m more used to two strokes and this would only alter the off idle mixture and turning it an extra turn would lean it off so I’m a bit unsure with this.
Maybe the P.O. has tried to lean it off this way?

E18 is 3.5 turns, then the next 2 columns to the left are the same (see arrow) then right column ( E01 06 42 28 30 ) is 2.5 turns. Assuming E02 (UK) model, 3.5 is correct (or even E34 Italy (both mine are Italian imports and my previous one back in the 90's was Italian as well!) that seems to be the most common imported from Country.)

UB