hey, that k&n might flow a different amount of air than your stock filter and that is the main reason people say tune the carb. the most reliable way is on a dyno and then read your new plugs after your oil change. i was able to find this posted by Scar at VTXCAFE.com...well that wouldnt fit in this post so go here:
http://www.vtxcafe.com/showthread.php?t=1914 you will find a lot of info there and it seems to me like he knows exactly what he is doing as far as finding out what works and what not. I would sugest you blow out the old paper air filter with compressed air in the opposite direction that the air usually flows through it, or grab a new one and use that to try and get the A/F ratio in a more acceptable configuration or see if it helps at least. That K&N has oil that may or may not be the best stuff to put into the intake. I try not to use them even though they get more power. Maybe from leaning the mixture out a lil bit...They may flow more air but do they flow more fuel is the question. As far as your spark plugs go id put something close to stock ie,type -copper, platinum, or irridium and whatever gap and spacers if any that stock plugs use. Ignition systems are designed to work with their respective plugs....vice versa. Changing type will likely cause problems in that area. unless you upgraded ignition system. OEM replacement NGK plugs and wires should work well. There should be a screw on each carburator, makes sense to me. What i got from reading around is pull the jet 2 1/2 turns back after you lightly put it all the way in, dont put any pressure, as in dont tighten it like a bolt. Just get it all the way in there. Not sure if thats the stock setup or what....id write down how many turns each one screw in when you pull it apart,so you could put the stock pipes and stuff if all else fails.
Ive looked behind a K&N I was using in my convertible FC3S connected to the air flow meter and didnt like what I saw...maybe I used to much oil...wanted to use enough.....any ways red stuff (oil)was all over the place in there and something was telling me that it was gonna be bad for the poor thing:turbo housings, thermal coating on rotors, series 4 lower intake, series 5 upper (variable dynamic chamber) intake and fuel rail, injectors flow tested and cleaned, Racing Beat header, Magnaflow 2 1/4 in after-straight-cat single exhaust system (driver side)=), NGK plugs and wires. no emissions exept cat. manual steering rack, A/C removed along with everything else. New fuel pump and all new racing mounts for oil cooler, motor, diff, tranny, ect..ect..oh and a ACT stage 3 clutch. Tokico struts. Hawk racing pads up front. BBS wheels....man that was a lot of fun smokin civics and Integras. I used mobile 1 2-stroke in fuel. So spark plug cleaning was regular. Your bike would be happier with you if you put the new ones in it. and have it dyno tuned. after you get it running properly or now...to keep from buying multiple gasket kits. Tinkering aroung to see what works before hand is a good idea if you think you can put it back together right.....id consider tuning it for long term reliability rather than other purposes.....
I could write another entire page on "tuning techniques", but it has already been done in what I consider a comprehensive and accurate manner... use it as your tuning Bible -- Factory Pro
http://www.factorypro.com/tech/carbtun.html
