>>1609921>What metal piece?It looks similar to this. You bolt the caliper to it then you insert this into the frame.
>>1609931I'm not exactly weak handed, I fix machines for a living, and how tight does it have to be anyway? What's confusing is that there shouldn't be any force on it in a direction that would make it go off-center in the first place.
I'll just have to pull it off again and add some Locktite to the threads. I've got to go replace the rear tire now anyway after today (sidewall puncture).