another spitting and supttering question

[birdaprey]

I have a 2002 Hayabusa with Yoshi race slip-ons
a BMC street air filter. I put these on at 200 miles I now have 14,000 miles

my question is I was told i didn't need a power commander with these mod's ( and it seemed that it was doing fine up to around 8,000 mile's. then the bike started spiting and sputtering at around 2000 rpms when taking off from a stop...(funny thing is it didnt do it all the time) well I went a head and bought a power commander III usb and loaded yoshi slip on map.... (this did not seem to help at all)
finale after a year I started adjusting on the power commanders buttons, in the low rpm range. I made it richer up to 6% and it has seemed to fix the spitting and sputtering but it dose seem to still feel a bit funny. what do you think caused the bike to all of a sudden start acting up... and why did it fix it when I riched up the low rpms?

 

[05BusaLe]

Check the fuel pressure! Sounds like the pump is not moving enough fuel!
Also check the fuel filter!

 

[SnapAttack]

(05BusaLe @ Sep. 03 2007,12:34) Check the fuel pressure! Sounds like the pump is not moving enough fuel!
Also check the fuel filter!

Also run some injector cleaner (I use Redline or BG) in concentrated dose through the tank. Check inside the throttle bodies for build up around the butterfly. make sure the TPS is in sync. REplace the air filter with a stock one as you might be running lean even though you adjusted. if you have a TRE... remove it and see if that works...

Members correct me if I'm wrong but that's what I would do since it doesn't cost much to do.