I've thought about fitting a BMX disk brake to one of my old bikes for safety in traffic. I don't know if that is practical, or if it has the requisite performance, but for $40 it might be worth a look. These are made for mountain bikers and I have to imagine they can put high demands on their brakes. I've made quite a few hubs out of aluminum, and steel and I think that would have to be done to use any single, or dual front brake. These brakes may be junk, but I would like to have one in my hands to see.
https://www.ebay.com/itm/Bicycle-Fro...SIV:rk:38:pf:0
https://www.ebay.com/itm/Bicycle-Fro...SIV:rk:38:pf:0
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