Guessing you haven't done this yet, but both the flat-mount road caliper and post-mount mtb caliper would need to use the same diameter pistons for this to work nicely.
Thanks, no I haven't. But if I ever do I'll bear that in mind!
@russmeyer started
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Guessing you haven't done this yet, but both the flat-mount road caliper and post-mount mtb caliper would need to use the same diameter pistons for this to work nicely.