Piston size effects the bias too. If I plan to do any hard high speed braking, I dial all the rear pressure or it wiggles alot when you hit it, I know it is a wiggle away from getting ugly. Around town/low speed, I add almost all of it without rear lockup. My rears wheels/tires are wider than the fronts too. I am also running the stock proportioning valve after the adj one. Don't know if that makes a difference.