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Two teeth broken off 12T sprocket in Performance 11-28 cluster.
From http://picasaweb.google.com/thisnthatntother/Fail?authkey=8ePsxVY29kw#5236063490703895186 as of 2008/08.
Broken after approximately 6500 km, 2 years.
Rider weight approx. 80 kgf.
Failure symptom was crank felt loose, but only in this gear.