The IT175 thread reminded me of my YZ125 experience. The transfer ports were so mismatched, left vs. right that bike had no power, at all. Porting was what let the big boys run away from y'all. Here's the scene, a lowly engineer says this will work great. We'll leave the Suzukis in the dust with this. The factory was unable to reproduce the engineer dream, failure often ensued. Get out your rattail files, ease transitions, balance right and left, then get into the mind of the designer. This is when my buddies take their cylinders away from me. Go solo, figure it out. Was the designer going for a Schnurle effect or stopping the incoming transfer ports to each other, a Honda innovation. Resist the urge to hog it out. Velocity is more important than volume.