When bleeding my brakes on my 2000 M750D I noticed the brake bleeder fittings require different size wrenches, front and rear. The front took a 6mm which fit well. But I could never get a proper fit with the rear brake bleeder: 10mm is too small and 11mm is too big (even a 7/16", which should be in between 10mm and 11mm, was too big). I was able to use the 11mm, but it was so loose that I was worried about stripping the bleeder. Is this an idiosyncrasy with my bike, or is the size indeed an eccentricity? Does anyone know what the rear bleeder wrench size should be?