Hello everyone, I am a new member here. Nice place you have; I have been reading on here again and again and figured it would be the right place to ask you about a problem I just can't get sorted out myself. It is about bicycles and disc brakes. I have an aluminum track frame that I want a rear disc brake on. The frame does not have disc brake mounts. However it does have a mount for a "normal" 1-bolt road type caliper brake. The frame looks pretty much like this: http://i.ebayimg.com/t/Unknown-Lv2-55cm-Track-Frameset-Cane-Creek-Headset-included-/00/s/MTIwMFgxNjAw/%24(KGrHqFHJEgE-muhtjmCBPz8dLEK%2B!~~60_57.JPG I have searched the internet over and over for retrofitting disc brakes, have looked at countless adapters and diy-solutions. I have made some drafts of concepts I have been thinking of, here they are: I think the pictures are basically self-explanatory, so I will just ask you what you think of these designs and where you see possible drawbacks or disadvantages. The adapting system should be as light and as safe as possible while not altering the frame. I would be very grateful for any input on this. Thanks so much!