im doing a bit of street on my norco 2003 two 50 and right now im runnign v brakes on the rear and i was wanting to put my 6" hayes mechanical on the back but it doesnt work. when i mount the caliper on the frame and then try to put the disc in the disc goes to deep in the caliper and bottoms out on the bottom making the rear wheel not move forward and then i cant put the rear wheel in the full way. (these are horizontal drop outs by the way). i was just wondering if i need a special mounting bracket for it to extend it outward or something or what to do. i also tried putting the rear wheel in first with the disc and then adding the caliper but that doesnt work either. Just to add if it makes a difference that the disc was originally bought for the front and is meant for the front. im not sure if there is a difference, also i used it on the front for a long time.