Originally Posted by
Andrew R Stewart
...Most people will opt to just encapslulate the rust with Frame Saver or other coating...
+1. The red stuff is just oxidized iron. It's the product of rusting, not the cause of it. It can exacerbate rusting if it gets wet and holds water. Get all the loose stuff out blowing out with compressed air and perhaps using a steel brush, and then apply the Frame Saver.