you can remove the threads if you open up the motor, but vex doesn’t sell any replacement threads. Someone, I believe it was @technik3k, found a very close replacement part online that is almost identical to the threads, just using 6-32 screws. Here is technik’s post about this. I don’t think they are technically legal, but you aren’t gaining any unfair advantage by doing so, and its not like inspectors are going to make you show them each of your motor threads, so I mean…