Start small and work your way up to 6mm. The rear of the bridge needs to be 8mm if you want to use a brake with a recessed nut. The hard part is getting the drill in place as there's a big seat tube in the way...
@pifko started
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Start small and work your way up to 6mm. The rear of the bridge needs to be 8mm if you want to use a brake with a recessed nut. The hard part is getting the drill in place as there's a big seat tube in the way...