Rejetting an 07 GS500F

[The Buddha]

OK it was lean to 1/4 throttle and you closed 1/2 turn the air screw and it got better - well there is atleast 3-4 things wrong with that sentence.

You made it leaner by turning in the air screw ... cos ironically the air screw is actually a mix screw. Its a tapered oblique obstruction in a tiny little fuel passage.
In - more of the thing enters the passage cutting down the flow. Out = it gets out of the way more and is a flow increase.

Pop on shut throttle etc etc is not lean. It could well be rich. Popping on acceleration = lean. Its called a lean Misfire. Pop on shut throttle may be normal. Its a 2 cyl with an unequal length exhaust pipe. Definetly can pop on shut throttle.

And air screw really controls idle and seriously gets very ineffective ~2000 rpm max. You should not be adjusting that for 1/4 throttle response. You need to adjust it for idle mix pretty much and nearly nothign else.

Really to 1/4 throttle you need to look @ float level. However leave the idle screw where it is, and after setting the float check it and adjust it.

You need to jet it top down, you change the lower adjustments only after you get the upper ones dialled in. Of course you miss the jetting at the low end in the begninig, you wont even get it started, so its a semi self defeating method.
But after you have it running, to get it running better - this is the order you ideally set them in.
Mains, and yes your mains should be fine as long as you told me what you were running.
Needle - yea - see above.
Floats - OK you need to adjust these right.
Pilot - no problem here - only 40 will work with the GS carbs on a stock motor.
Air screw - adjust away for idle issues.
That is the order to fine tune it. That is the only way to get it in 1 pass. Else you will have to fiddle many many times.
Cool.
Buddha.

[steguis]

Ah thanks...I'll check again. She definitely felt better yesterday, no popping, no dead spots, accelerated fine all the way to 10K and idle sounds nice and smooth.