1999 640, ids2 quiet core 10 discs, stock airbox cover, no snorkel but airbox top hole maybe 1" wider. I'm running: 4.5 clip 162.5 main 47.5 pilot I feel the main is one or two sizes low at this time. Other than that it runs pretty good. I can still hear it from 100ft away but it is a revving kind of sound and not a popping. One of the problems with more open exhausts is that it amplifies combustion defects and often that makes a bike sound much louder than normal. Seems if set the mixture solid at the first rich yellow (jet4power) I don't have any popping or uneven sounds, and power is nice and smooth. It's really crisp at off-idle, falls a little flat as my mixture drops off a bit higher in the throttle and solid yellow turns to green/yellow flicker. Needs more fuel there, probably a main or two. If that doesn't hit that area then I"ll need either another needle or I will have to tune the spring for a more appropriate slide position relative to that particular vaccuum.