I was wondering what I should run for jetting. I have a 07 YFZ 450 with a full LRD race pipe, K&N air filter, and a LRD intake. I have a jet kit and have tried evey combination that the jet sheet tells me and I just seem to get it right. It's either running lean or to rich. I can't get it right. I'm sure the jetting would be the same with other pipes on YFZ's so any help would be great. Thanks.

no pipe is the same, i cant tell you the right jetting, but the people on yfzcentral.com will be able to easily

I replaced the needle jet with the YZ style and it made jetting a little easier along with richer pilot jets and putting on the "zipty idle screw".

Have you tried adjusting your needle? That is one other easy way to adjust your fuel ratio. The only other thing I can say is try just changing your main jet which ever way you need to go, bigger if you are running too lean and smaller if you are running too rich. The only thing that truly matters is that you don't run to lean and blow it up, you want it a nice golden brown after getting it nice and hot.