I have the CBR 600 carbs. I ride at 3500' & above. Right now I have the YFZ filter, and 158 f & 160 r jets. I haven't had a chance to do a good plug chop, but just riding it hard and checking the plugs, they look faily good. It has excelant throttle responce, and pulls hard all the way to shiftout. Just need to know if I'm in the ballpark with the jetting I have now.