i love these mini-brute motors; we use these in three of our race classes. but there is one problem, the motor shaft like to break loose & slide forward into the drive gear. i've had at least three motors break loose & had to toss them in the garbage. but i think i have a solution to this problem.

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i bought some bead crimps from michaels because they looked interesting. one is them is .077", the perfect size for 2mm shafts. i put one on the back end of the shaft & pressed it in with my bench vice. not too deep or it will bind. i trimmed off the excess & it looks pretty damn good. you can find these in the bead section at any craft store.