I am trying to fix a stumble my bike has when cruising at medium revs (55-60 km/h in 3rd gear - 15/48 gearing) the bike pops/stumbles when on the low speed jet. I have tried adjusting my fuel screw everywhere from 1 through 3 turns out and nothing seems to get rid of this. Do all XR650R's do this? Am I being to picky or can this be sorted? I have a 68S slow jet, 4th pos on B53E needle and a 175 main at sea level.