Ray , I too have those Avid shorty's on one of my bikes , and also sqealed like a pig in heat .....so I switched to Koolstop dual compound pads ...still sqealed but not as bad , no matter how much I adjusted, nothing could really stop the racket ! , but quite quickly over a period of maybe 3 weeks of use , the noise went away !!!!
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Velosophy#1: It is better to have a bicycle and no money , than money and no bicycle ! Velosophy # 2 : "Winning is simple, but not easy." #3: "Give a man a fish and he shall eat for a day , teach him how to fish and he will sit in a boat and drink beer all day"