Going with a larger rotor or replacing your current mount, then the Reverse Components Disc Brake Adapter PM-PM +20mm Front or Rear is the perfect option.  Available in various colour options and sizes to suit your brake setup.

With the PM-PM +20mm brake adapter you can increase your disc size by 20 mm.
This means, if your Post Mount (PM) brake mount on the fork or frame is designed for a 160 mm brake disc, you can mount a 180 mm disc with the installed adapter.
The same applies to other disc sizes.

• PM brake mount 160 mm + PM-PM +20mm adapter = brake disc size 180 mm
• PM brake mount 180 mm + PM-PM +20mm adapter = brake disc size 200 mm
• PM Brake mount 180 mm + PM-PM +20mm adapter + 2 spacers* = Brake disc size 203 mm (*With one spacer per mounting side with a thickness of 1.5 mm)
• PM brake mount 200 mm + PM-PM +20mm adapter = brake disc size 220 mm
• PM brake mount 203 mm + PM-PM +20mm adapter = brake disc size 223 mm

When using the PM-PM +20mm adapter, longer mounting bolts are required, which are not included and must be purchased separately.

• Weight: 13g (+/- 5% weight tolerance)
• Material: Aluminium