2001 monster 900S that runs well but has a stumble off idle when I blip the throttle. I have a K&N filter and LeoVince high mounts mufflers. All else is stock as well as stock ECU. I have VDST software, trim is at 20 and the throttle angle is 2.6 to 2.8. I have not reset the TPS and it appears that is has never been touched as the paint is still on the screws. Bike has 10K on it and the belst and valve clearances were just done. It's pretty annoying and would like to figure it out. Bike runs extremely well of idle. Any thoughts?