Inverse shim?
Only necessary if he uses 30.0mm clamp. A normal shim will do do fit a 31.8mm clamp to a 31.2mm tube. 0.012" brass or steel should be easy to find.
I've got some brass somewhere, I will give it a go.
@spotter started
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Only necessary if he uses 30.0mm clamp. A normal shim will do do fit a 31.8mm clamp to a 31.2mm tube. 0.012" brass or steel should be easy to find.