When setting the low needle do you prefer it to be rich enough that you can gun it really fast and keep the engine running, or have it lean enough to not have any 4-stroking when throttling back to idle? I can't seem to have both.

I set mine so that it will accelerate without hesitation. If you get leaner, it will become difficult to start. Then I set the HS.

Unfortunately, our carb settings are always going to be about compromise? That said, trying to completely tune out 4 stroking is going to be nearly impossible. Most are single cylinder, and it's a 2 stroke engine. They just do that?

So to answer your question, I'd be looking for a quick/smooth transition from idle to WOT. After that, it's time to go fly it and see how it works.... That's my vote anyway. -Al

Those are two really good considerations...easier to start when fatter and fly it to see how it runs. I usually comprimise, but occasionally, on certain engines, I have nailed it (no 4-stroking AND quick acceleration w/o quiting).

A higher prop load will often help with the mid range burbling in flight. I agree with setting the engine for best response even if that means putting up with a rich mid range. Engines that are slightly rich rarely quit, but a lean one can. Plus if you set it lean, sooner or later you will hit the throttle too fast and the engine will quit, probably at a most inopportune time.

What we really need is a Walbro type carb with a midrange adjustment needle. If someone ever made one, they would sell a bunch!!

There is a way to lean out the midrange a bit, but it is a bit tricky to do. PM me if you are interested.

AV8TOR

In addition to the previous comments, with some carb / engine combinations, the best LS needle setting may be very lean. Even to the point where the engine will not take throttle until it warms up a bit. If the LS was set any richer, the midrange was way rich. My DA50 was this way but most engines adjust the low needle as described above. With regards to the original question, its really more about the transition from low to full throttle than any other point.