2nd DO NOT wast your money on a k&n filter A stock filter flows just find. Go on to Brock's site, He even states that a stock filter is all you need, Why would want all that oil and element crap on your air filter! Suzuki, did there R&D with the Hayabusa, the only reason certain things are the way they are is emissions. Send me a pm if u want to try a good base line map. 
Well, with all due respect,, I have never read a bigger load of crap that what you just said there. For one; Brock's website is outdated and needs a visit by those that have been in this a while. I respect Brock, but I don't know who last edited his findings. There is plenty in there open for conjecture.
[size=06pt]One of the modifications I suggest with my pipe package is to the stock air box. This brings me to some valuable information that I don’t mind sharing. Listen VERY closely; the new machines of today enjoy nearly nothing in common with the old KZ’s, GS’s and even GSXR’s of the past. The new bikes are nearly perfect. Unless your modern day rocket is parked on a dyno, nine out of ten changes that you make to the stock configuration will probably result in a LOSS of performance and/or reliability. It takes a pretty brazen individual, from the confines of his own garage, to second-guess a multi-million dollar research and development team! Leave your bike alone except for the changes I suggest, and soon we will all be outrunning the guys who try to think alone. It will be our own little cult of fast guys on stock bikes, kicking the crap out of anyone who dares sit still next to us…Anyway, I fought the airbox mod tooth and nail. If these bikes can run nearly 200 mph through that little square hole with a flapper valve in the way, who am I to change things? The bike only breathes through one cylinder at a time, right? This should be plenty. 
But, after numerous dyno pulls and trips to the track and ONLY in conjunction with the dynojet Power Commander II (which I personally wasn’t convinced did anything but slow me down at the track, until I used one in conjunction with a Dynojet model 250 and A/F sniffer!), the airbox mod I detail in my pipe literature works well. The around-town drivability doesn’t suffer, thanks to the PC-II and the max power output is definitely increased. The StreetSmart TM exhaust is over-sized to allow the ram air and box mod work to function at maximum potential. Of course, any hopes of passing an emissions test are thrown out the window with the removal of the stock system.[/size]
These are motorcycles that were bred for racing and simply removing the small area of your air-box and replacing the stock filter with a better breathing device will not hurt your ability to pass or not pass an emissions test; nor, will it effect your "streetability".
In some of the article I read on his web page, he says that the TRE is for the 2000 and the 2001, we all know that the 2000 Hayabusa was NOT restricted, so, this was erroneous information, that year bike had no need for the TRE and this information begs to be re-written.
My advise is to go small airbox removal and the "BMC RACE" filter. Make sure it
IS the "race" and not the basic BMC model when ordering. No amount of oil bath will ever change the huge amounts of increased air you will receive. It has never bothered my bike, not once.
You won't "need countless hours on the dyno" to get your bike right. Don't be afraid of these simply mods, they will only make your bike run more spirited, not lethargic. And, that's why you bought it right? For the horsepower and the thrill?!
