Originally Posted by
SuperRecord
chain stretch is likely another reason
If you have done just a dozen rides or so and those haven't been like 100 km each or in muddy/sandy conditions, there shouldn't be any chain stretch (that's wear actually) to speak of. Also, in my experience, chain wear doesn't affect shifting as much as cog wear does, since they have individual teeth specially profiled to help the shifting, and those don't work that well anymore when they're worn.