Boule’tard wrote on 05/09/12 at 13:27:54:That's a very good question, which can be simplified by forgetting the stuff about the valves and the needle/needle jet/slide etc.
I am super rusty on fluid dynamics and have no time to research it. I bet Oldfeller can 'splain it. Nudge nudge.
OK, here's my take on the whole mod it to make more power thing.
We tell them to rejet.
We tell them to put on free flowing muffler.
We tell them to put on a free flowing air filter.
You guys are getting tied up in your knickers over the order of things like A causes the need for B or C. False assumption there, you can do them in any order but you will likely wind up doing all of them as they complement each other's improvement effects.
Jetting generally gets tossed to the end of the bus since you fine tune the jetting AFTER you finish muffler and filter mods (or you get to do it two or 3 times as some of us have done)
I wish carbs were that good as to be totally self adjusting -- they aren't. Sorry.