You won't feel much of a difference without a tune.
What I would recommend:
K&N Filter and Mod your airbox (there are writeups on here, you cut the bottom hole in the intake box to be larger).
Then while it is out, Take out the ECU and send it over to TurboJoe, he is a car/bike tuner out in CA.
He will flash the ECU for your exhaust / intake, and remove all the restrictions.
Then your bike will feel like a completely new bike, way more power especially in 1st and 2nd, and it will take full advantage of your mods
-B
Here is Joe's Facebook, he has done a few tunes for me all of them have been perfect, let him know Branden sent you.
https://www.facebook.com/turbojoe.tuned.9
Hi Branden,
I have a Yoshimura slip-on exhaust on my FZ8, but no air intake mods. I bought a Dynojet PCFC this week and much to my disappointment, there wasn't a specific fuel map for my set up. After stumbling across this thread however, I wanted to know if you think I should just return the PCFC and send my ECU to TurboJoe or take my bike to my local shop and have them tune the bike with the PCFC. The unit is supposed to come pre-loaded with 10 different maps, but I don't know what they are like or if they will even make a difference.
Thanks!
some oil on it is normal from blow by. Just order some AIS plates for 20$ off ebay and install them. They are a pain to do because of the limited space, but once they are done, you never have to worry again, and it makes accessing spark plugs much easier.
-B