I am looking for an adapter plate to convert rear caliper brakes to 990 brakes. I purchased an inexpensive bike for my daughter who was just learning to ride and she is now complaining that the brakes don't work. i have changed pads and that did not help. It could use a better brake lever which I am going to replace, but I definitely feel the brake s need an upgrade. I have a brand new set of Dia-compe 990 brakes and I would like to use these since the bike has a rotor on it. I know that these were sold in the past cause I sold them at a shop I worked at. Any help finding one would be appreciated.