Hi Folks, 2006 DRZ400SM with tt 39fcr. Was running stock header with pro circuit slip on 165 main pulled hard all the way to redline. Installed full Leo Vince system with no baffles or spark arresters--straight thru. Now when I go full throttle from 3/4 to full it starts breaking up on top as though it is too lean. JD says use 170 main with cams and free flowing exhaust. Should I go 170 or 180? Has 3x3 and KN filter. Engine is stock internally.