After having a 03 KLX 400 with lots of mods, i find the Buell a pretty big thumper. I just ordered the D&D powdered black exhaust system and custom intake from ebay. Im wondering what stage of jetting im going to have to do and if i could do it myself? Any help would be greately appreciated!

Intake and exhaust
48 pilot jet
180main
Iridium race plug


Loudest bike with the exhaust

I finally just figured out a couple weeks ago the combos for jetting with this thing. Took me some experimenting, but it's final tuned in. I believe that the stock jetting is a 170 main and a 42 pilot. Earlier models might have a 165 main. maybe 2004 and older. When I got the bike a month ago it had a no restriction knn air filter with the stock exhaust which was extremely lean with the stock jetting. So i decided to just get an exhaust system before i messed with the jetting. Bought the Jardine exhaust. Ridiculously loud. Louder than any bike ive heard. I love just whampin on it when i go by a bunch of harleys sittin on the side of the road because they all turn, thinking its some huge power bike haha. So with the least restrictive intake and exhaust i new i had to go big. ordered a 180 main and a 48 pilot. So they send me a 180 and a 46 bc they said id never need a 48. Well i put the jets in with the Iridium racing spark plug. Still lean. So i asked for the 48 again and now it runs good. The 46 ran smooth but lacked a little power on bottom end.

Heres the thing. The exhaust and intake seemed to reverse the power curve. Now all of the power is on the top end and bottom isnt what it used to be. Also sucks the gas pretty good, obviously. Good luck let me know how it goes.