Hi i bought a magura Louise fr from ebay and it arrived this morning , it looks good and is in good condition so i fitted the rotor and put the caliper on my forks but the rotor is hiting the back of the caliper as if its to big. it is a 180mm magura sl rotor that is supposed to go with the brake but it hits, i tried a 160mm rotor but it only comes half way up the pads so i think the caliper is defiently 180mm like it was listed as. I've got echo control forks and I've had a 180mm mono trial which worked fine so i don't think the disk tabs welded wrong. please help this is what the brake looks like