Last night I was riding, and did a sprint up a hill. Came up to a stop sign, and my rear wheel came loose in the dropouts. Took off the track nuts, and the serrated section is completely smooth. Could it be from over torquing the nuts, or did it wear our from age? These were cheapo oem nuts that came with an Alex R450 flip flop wheel. Should I get a different set of serrated nuts, or is there a better design out there?

Dave