I typically break mine in, and then start leaning it out. I start with the HSN, and then the LSN, I do some high-speed runs (leaning out 1/4 turn) until I lean it too much, then go back about 1/2 turn. Then, let idle for 10 seconds, and give it full throttle, and begin the LSN leaning.

You are going to find a slew of responses. The bottom line is that tuning is really not that difficult. If it's sluggish and lots of smoke, it is too rich. If it's choppy with little to no smoke, it's too lean.

And yes, the small screw is just the idle-stop. I would not mess with it unless you have problems starting or it won't idle right.</p>