I’ve got M785 XT brakes on my bike, had them for around a year. All that time they have never seemed right, in that they deteriorate very quickly. I’ve bled them at least 5 times and I’m very thorough with it, using every trick that’s been on any STW thread, the epic method, the Shimano instructions – everything. After bleeding with the bleed block in they are rock solid. After putting the pads and wheels back in, but before riding anywhere, they are rock solid. Then I ride it and after not long at all they are spongy as **** again, and remain that way. I’ve tried at least half a dozen different pads, sintered, organic and mixed, and it makes no difference.
What’s going on with them? Can they leak in use and do this? I cant think what else it could be?