Versa planetary lock up

We are using versa planetaries for the first time this year, and one of the ones on our shooter has pretty much locked up. Took everything apart, no visible damage when looking quick. Reassemble and when spinning he output shaft by hand can feel a hard spot.

To make matters worse the 3:1 s are out of stock.
Which brings me to my next question any teams have 2 or 3 they can part with? Obviously we would pay for the parts and any shipping

Do you remember what happened before it locked up?

We have a couple extras, but we’re in Canada. If you’re really out of luck PM me and we’ll figure it out.

We were taking a couple test shots with the shooter and thought we heard a noise, but weren’t sure. The shooter worked after said noise, this was Saturday, this evening wanted to check how it would work with intake, and when we applied power to the motor to check rotation it made a small spark but shaft didn’t turn.

Do you have pictures and/or a detailed description of what you’ve tried? The people of CD may be able to fix your gearbox, if only there is more information.

No pics as there is nothing to really see. Disassembled, looked quick for damage, regreased, reassemble. Spin output shaft by hand, has a stiff spot. Take back apart try different ring gear, same result so telling me an issue with the sun, or one of the planets


Did you verify the motor is working correctly stand alone?

Does the gearbox rotate smoothly with out the motor?

Depending on how you were using the gearbox on your shooter, it could of damaged a bearing in it.

Does your shooter directly drive the wheel?

Some pictures of the shooter type, or description can help.

Things to list could be…
Shooter type … Flywheel , two wheel, (benchtop grinder)
Motor Type … CIM, BAG …etc.
Ratio, which I believe you stated as 3:1
How power is applied to motor… talon, victor… etc.

Only option if you wish to continue troubleshooting is with the other gearbox.

Move the gear set or ring gear form one to the other. One thing at a time and see what makes a difference in hand turning the shaft.

Then you discover which part fixes it. Then compare the parts and see what happened.

Many times when hand turning and you hit a specific snag in the rotation. Verify location by going both directions. Many times some debris is in one of the teeth. A large amount of rotations before snagging is something in the ring gear. A short amount of turn usually is in the sun or planet gears.

I have used these gearboxes in many various ways and some of time we were rough on them. They tend to hold up very well, but not bulletproof.

Good luck with this, I have many parts to those gearboxs and would gladly send them. Though I am one of the further points to offer so far.


Still need to try the gear set in old ring gear.

Though this is starting to sound like either the output shaft is bent / damaged or the bearings.

Still need to try to hand turn without the motor. Just take off the plate & motor assembly.

Or perhaps the motor adapter set pin is hitting something inside.

A quick look inside?

You might have to devote some time to doing this.

Did you clean the teeth on the ring gear before you reassembled?
What are you greasing with?

A piece of chipped gear stuck between teeth can be quite small.

When the output shaft assembly is removed does it turn freely?


Have you inspected the gear teeth? Do all of the planets spin freely on the carrier plate pins? Are all of the carrier pins still fully pressed into the carrier plate?

As always, feel free to email me at the address in my signature and I"ll help you sort out any issues.


At tiki, the spark was due to the gear box being stuck, and we were sending power with jumper wires with clips directly to a battery. So the stuck box was causing a bunch of current at the motor.
We did have the motor (775 pro) off the box when we were looking for the issue. I didn’t check for bad bearing or bent shaft but will this evening.

At Aren I sent an email to vex about this email address is same as my name here. My contact info is included in email perhaps you could give me a call?

We had some issues with the 775pro and VP randomly loosening up and loosing friction (The gearbox would spin and the motor would stop).
It had something to do with the set screw.

We decided after awhile that it wasn’t worth using a atm out of stock motor, and an out of stock gearbox so we switched over to a 1:1 mini cim setup. Kind of sad but there was really no other good choice.

I have no clue what the issue was but it happened on both setups. Originally I thought it was bad assembly but after further inspection it was not.

We had some smiler problems with the 3:1 gearboxes this year also. they never fully locked up but after about 3 hours of running the pins that hold the pinion gears started to work their way loose. we caught it but i imagine if we had let it go the box would have locked. I would take a look at those pins and make sure that the tops of them are a little below the top of the pinion gear.

When I had it apart yesterday I didn’t notice the pins sticking higher than the small planet gears.

Oh and it was asked earlier what type of grease… White lithium grease per vex website

Planets don’t normally skip when a tooth fails like in a spur gear trans. Planetarys will eat themselves quickly.

I’d put money on Sperkowsky being on the right path.
I’d suggest using a dab of locktight on the set screw to make sure its secured. We had run into a similar issue when mounting bag motors to the versaplanitary transmissions.

If you are referring to the set screw that goes into the input coupler it was loctited as we assembled the gearboxes initially. When we disassembled last night the old loctite was cleaned off the set screw and from the hole in the coupler and more loctite was applied.