Ok, I've looked around and found different answers to this question, so... what's the deal with this drop-in filter? Do I have to rejet or not? K&N says you don't have to, have seen that repeated other places, but then some people say it runs lean. Are we talking "just a tiny bit so that you could ignore it unless you're racing lean" or "lean enough that you want to rejet to prevent damage kind of lean?"