Originally Posted by
Velocivixen
Is the cassette you installed the same general sprocket size? Wonder if the guide pulley is rubbing on the bottom edge of the cogs? I'm definitely no expert but just a thought you could check.
That was my first thought too.
My second thought has to do with the chain. Did the OP install a fresh chain to go with his new cassette? A worn chain on a new cassette might do that.
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