Is your bracket mounted to the seat tube? Have you read the [ahem] directions? (That wasn't me saying that) I suspect it was intended only to be mounted on the seatpost, which is obviously a smaller diameter than the seat tube and therefore may deliver the needed clearance. Here's my setup. I am actually using the bracket from my first Kryptonite U-lock--the one that can be defeated with a bic pen. The bracket that came with the new one was not as user friendly.
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