VEX V5 Motor Threads

Hi all.

We recently recieved our v5 shipment and while putting motors on we ran into an issue. The threading on the inside of the motor came off when we unscrewed the motor and now it looks like this:

The bearing flat we used also has threads in it since we unscrewed. This can be seen in this image:

The motor has threads ripped out, and it looks like this:

What should we do?


Team 1516B
Cal High Robotics Fightin Grizzlies

1 Like

This happened to our motors as well but it should be okay to use still. Just make sure it is aligned properly before you really tighten it down and I would recommend using washers on the screws just to make sure they won’t loosen.

To align the motors well our team has been putting the axle into the motor and screwing in the one hole that actually works so that the threads will still line up with the holes in the c-channel or whatever you are screwing into.

1 Like

It really sucks how weak those threads are, I recently lost a motor to them as well. You can still use the motor if you must, but it won’t sit as securely as before

1 Like

This issue with broken motor inserts was discussed back in this thread:

If current inserts are unusable you could replace them with the standard 0.5" standoffs, but that could put motor plastic base under additional stress, which could break it in the worst case.

I found a replacement part that is functionally similar to the vex motor inserts but has stronger walls, since it uses 6-32 screws:

Some people may question its competition legality, to which I say that until VEX sells motor insert replacements at a reasonable price or exchanges broken ones free of charge, you should not feel bad about using a third party replacement part.


Plus, if they are attached so that the inspectors might not be able to see how and where they are attached, they might not be able to call you out on using them.


Would you want to post this on the official Q&A?

Unfortunately, I can’t, because I am neither primary nor secondary contact for our club and, also, I don’t think GDC will feel comfortable answering this question.

Same as with potential ruling on partially threaded screws and 393 output gears I wouldn’t want to ask the question if there is a chance they will discard a precedent of those parts being allowed in previous seasons, and rule them illegal going forward.

1 Like

Sadly this is only a problem because of the 8-32 screws. This is something vex really cant help unless they change the put extra metal around the corners, which would interfere with bearing blocks.

To the OP I would stay away from screwing motors in on the same side as the bearing block since the threads on the motor dont like to fit inside of them (from my experience).

1 Like

Screwing them in on the bearings was actually how mine broke. It took very little force, no more than normally screwing it in, so it is extremely easy to break those threads