Well after I destroyed my derraileur the LBS said my chain was trashed also and went ahead and replaced it. 3 months of riding on my new bike and the mechanic said chain was 40% worn. Is it normal to for a new chain to skip on slightly worn cogs? It was skipping pretty badly. Seemed to skip more in higher gears though which did not make sense to me because I would think they are less worn. Anyways I took a nice spill tonight when it skipped at a really bad time flying downhill. Little scraped up but the bike is fine Thanks for the help.