A bigger rotor may have the possibility of tearing the fork if it's not been designed for a bigger rotor, probably not but the manufacturer won't guarantee against it, maybe it'll just flex a bit much, you can get +40mm adapters too.
Why would a bigger rotor make a fork flex more?
@snottyotter started
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A bigger rotor may have the possibility of tearing the fork if it's not been designed for a bigger rotor, probably not but the manufacturer won't guarantee against it, maybe it'll just flex a bit much, you can get +40mm adapters too.