mtuts - the 30mm are machined, the 40mm are not machined.
You can run the 40mm with a brake, but it is not ideal and may squeal until the black finish has been worn down.
@TM started
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mtuts - the 30mm are machined, the 40mm are not machined.
You can run the 40mm with a brake, but it is not ideal and may squeal until the black finish has been worn down.