I have a seemingly simple problem but cant figure out how to fix it. After i engage my rear brakes they dont fully return to "open". I tried squirting chain oil down the brake lines but that didnt really work. And i tried to bend those metal pieces that seem to be acting as springs on the brakes, that didnt work either (i really didnt bend them too much, didnt want to mess things up even more). does anyone know an easy solution or do i need to replace some parts?