At Escapa, we have what your brake caliper needs to change sizes. The Shimano 203mm Disc Brake Adapter SM-MA-R203 allows you to mount a 203mm brake rotor on the rear wheel.
The brake mount on the frame must be compatible with IS 2000, and the brake must meet the postmount standard!
Technical Specifications:
Adapter material: aluminum
Screw material: Steel
Rear brake rotor size: 203 mm
Rear: IS 2000 standard
Brake: Postmount
Approximate weight: 28 g