Box Components

One Bmx Disc Brake Adaptor

What Our Gearhead® Experts Are Saying:

"This little adapter makes a huge difference if you’re looking to modernize a BMX race frame with disc brakes. It’s a game changer for control and consistent stopping in all conditions. The 10mm sliding dropout fit was spot on, but definitely read the compatibility notes—it’s not a universal fit."

Disc brakes aren’t just for downhill and trail riders—they belong on the BMX track too. That’s why we run the Box One BMX Disc Brake Adapter on race bikes we want to modernize without swapping frames. Designed to retrofit specific 10mm sliding dropout frames, this adapter allows us to mount a post-mount disc brake caliper and use rotors up to 140mm.

We love how this CNC-machined, anodized 6061-T6 aluminum adapter feels rock-solid once installed. It mates securely with both the hub axle and dropout, enabling precise braking and better modulation through corners and technical sections. If you’re tired of rim brake chatter and fade, this is your upgrade path to better control and more confidence on the gate and beyond.