Magura QM 45 Disc Brake Adapter

The QM 45 is a specialized adapter that allows you to increase your rotor size while simultaneously providing the necessary mounting points for Bosch ABS wheel speed sensors. It bridges the gap between your frame's post-mount setup and larger rotors, ensuring your ABS system remains functional after an upgrade.

While you technically could, it is designed specifically for e-bikes equipped with Bosch ABS. If you do not have an ABS system, you are better off using a standard Magura QM adapter, as the extra mounting hardware on the QM 45 will simply add unnecessary weight and bulk.

The QM 45 is versatile enough to handle two specific configurations: it adapts a 180mm post mount to accept a 220mm rotor, or a 140mm post mount to accept a 180mm rotor.

The QM 45 is engineered for Magura's post-mount brake systems. While it may physically bolt onto other brands, it is optimized for Magura's caliper geometry and the specific sensor positioning required by Bosch ABS, so we recommend sticking to Magura brakes for guaranteed compatibility.

Installation requires standard hex keys to secure the adapter to your frame and the caliper to the adapter. Because this involves your braking system, ensure you torque all bolts to the manufacturer's specifications to maintain safety and system integrity.