jetting confusion

[kdennan]

I am just a little confused. I have a new 05' 220 that I just stripped down and built up following Jeff Fredette's set-up video. I put a Wiseco piston in along with Boyesen power reeds, Uni-filter with airbox lid removed and an FMF gnarly/desert pipe. On the just kdx website under carbtuning, Canadian Dave says he is currently running a 45 pilot, 1173 needle in the 2nd position from the top and a 152 main. My conditions and altitude are similar so that is what I just did to my bike. Below his example there are starting points and for a like-modded 97-03 220 it says to run a 42 pilot, 1173 needle in the 2nd position from the top and a 145/148 main.
Stock jetting is 42 pilot, 1173 needle in the 3rd position from top and a 145 main. I would like someone of vast knowledge to impart on me what they have done as I only feel comfortable with testing the main. Since this is the first new bike I have ever owned I am very afraid of messing up.
My bike runs the stock 33mm carb and I have not done any porting of the cylinder.
Thanks
Kris

 

[Red_Chili]

You are close; unfortunately, many subtle variations prevent a "here is the perfect jetting for you" kind of answer. You have as close an answer as can be expected, i.e. a range of proper values for jetting. Start on the richer end of the scale especially to break it in, and the worst that will happen is, you may foul a plug. Go leaner incrementally until it runs great following the steps in the site you reference, then go one step leaner and you should experience a bit of lean stumble. Go back to perfect, you are done.