Hi, Just had brakes fail mot on. Pedal travel to much, no reserve travel. 1.9tdi x reg, Always been like it. Seen a few ideas on here about this. Story goes like this check over ready for MOT. Rear calipers seized on handbrake linkage, fitted exchange units also rear flexi hoses (inner and outer) and brake pipes. Was told that servo and master cylinder was changed for mot last year by previous owner and it does look like they have. Bleed all calipers no air in system. ABS working fine had pump running when bleeding. Pedal just like before. Pedal has a little travel with no engine servo, start engine pedal drops away and keeps slowy going to floor. road test brakes work fine. Effort on brake tester fine at MOT. Drive home brakes like they always have been. 1. All rear brakes new and checked so no fault there. So poss front brake fault. 2. Remove front wheels and check, replaced pads because close to wear limit, clean caliper,caplier carrier, slide bolts and discs both sides. Refit all parts. 3. Test brake pedal travel before fitting wheels. Same travel as before. 4. Clamp both front flexi pipes close to calpier, test again. Pedal travel now about 20mm after servo help then solid. So now is it a caliper piston fault. 5. Remove both calipers and fit a solid piece of metal the same thickness as pads and disc between piston and lugs to stop piston from coming out. pump brakes to get solid pedal. 6. Test brake travel solid pedal, start engine about 20mm drop with servo help. Pistons ok. no leaks dry behind bust seal. 7. Refitted capilers, Had my son press the pedal and then start engine when i looked to see what was happening, found that when servo help starts the caliper twists on slide bolts rubber mountings trying to push caliper outwards. Rubber gives a bit and piston moves more pedal travels. Tried with each caliper in turn and with each clamped off so one at a time. 8. Now for the question is this normal because the servo effort is to much, had same sort of caliper set up on my old fiesta many years ago but not this fault (smaller car less effort from servo). Any info would be good.