I ride shimano xt's and my front brake is not working properly. I have just bled both brakes and the rear seems to be working fine. The front one just doesnt have the power that it used to, actually it has no power left. It makes that horrible brake squeaking sound. The pad wear seem to be fine on both pads and they are also aligned. Sometimes i can pull the lever all the way back, other times the lever is ok. Any suggestions? thanks