Been having fits with a friends RV6A brakes. After couple weeks of bleeding to make sure no air, the crossover lines get air in them preventing co-pilot braking. My last time I cleared the lines and tightening all fittings, it happened again but this time upon landing and with even braking it pulls hard to the left. So, this time I replaced all the brake lines and the fittings for the nylon crossover lines (NSR tubing and fittings), disassembled, cleaned and rebuilt the calipers, installed new pads, the discs look good. Test flew yesterday, still pulled to the left, not sure about the air in the crossover lines, too soon to tell. The only thing left is the master cylinder?? Any expert input would be appreciated....