I have purchased a vintage Burley tandem and would like to change it from a road set up to a mountain type setup. I have a set of XT v brakes not being used and wanted to put them on the tandem. I have replaced cantelevers with v-brakes before with no problems but in this case when the brake is put on the bose the angle is vey wide open and there seems to be no space to set up the pads. What I'm I doing wrong?