Can someone explain this?

I'm not sure if this post should be here or in the jetting section - feel free to move it if it is in the wrong place. I was hoping someone could explain to me what each jet does and how they all interact with the fuel screw and needle on my 05' WR450. I have changed the pilot, main and starter and needle as recommended here and with my JD kit and switched out to a Zip-Ty fuel screw but haven't messed with the other jets. My basic understanding is that the pilot controls idle and low RPMs while the main controls the upper RPMs. The needle I would guess interacts with the main since it goes into the main needle jet. I'm not exactly sure where the fuel screw comes in. I know it adjusts the fuel/air mixture but is it for fine adjustments after the jets and needle and does it effect all levels of RPMs or only a certain area? And what about the leak jet and pilot air jet? Are those something that I realistically need to worry about? Also, is the starter jet actually just for starting the bike or does it have a another or different purpose altogether? I have a vague understanding jetting and I kind of understand the principle of it but I think if someone could explain more clearly it would really help me, and maybe others, with their jetting. Or, if there is somewhere else I could find out how it all works together just point me in the right direction. Thanks.


Wherever is fine with me but You'll probably get more answers in the jetting forum. I'm sure there's a sticky or some type of link to one of James' threads there. :cry: I'm not the jetting expert or a great typist, otherwise I would love to spend the time with you... :cry:

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