snapped motor shaft


This is why you should not lend your board to your elder brother.

He said this happened when none one’s riding the board and he’s just tryin to show-off a burnout. Doesn’t seem to be a case of chain-sprocket disalignment. A crack probably have propagated from the lock ring groove.

Will look for 8mm shafting in local hardware shops. Might need to go to a machine shop as well cuz I cant pull out the broken shaft. Already removed the grub screws but the shaft wont even budge.

Any similar case out there?

Any idea on how to lock-in-place the can without creating a groove on the shaft for the lock ring?

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I had the exact same thing happen, except mine was because the belt was way too tight. I thought of a machine shop as well but nobody wanted to do just one. I ended up just contacting the motor company and getting a couple more shafts.
Getting the shaft out was difficult. First I tried good ol vice grips but couldn’t get enough grip. Then I tried heating the can right around the shaft but I was afraid of too much heat damaging the can so I don’t think I got it hot enough to make any difference. Finally I just took a Phillips screwdriver and a rubber mallet to it and pounded the shaft out. Just don’t do it too hard, you don’t want any loose magnets.

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Heat wont really damage the can. Just maybe loosen up the epoxy holding the magnets. And for aluminum dont let it reach red hot. It doesnt need it. And let it cool in an oven (basically anealing it if u do end up reach red hot) drop the temp ever so slightly every so once and a while. This is to prevent warping. There is a certain temp u can reach w/ alu where u wont warp the can. Oh and to try to prevent warping only do the rod swap when u have both rods in case u decide just to hit the area w/ the rod and again prevent can warping

You can use washers, i can remember some motors having copper washers between the c-clip and the bearing, you can probably do the same but all the way up to the pinion. The pinion would then lock everything in place.

Anyway, what motors are those ? You can maybe find replacement shafts from the seller ? (i know that maytech sell spare shaft for their motors).

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Heat can definitely damage the magnets on the can.

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Will do exactly this. Thanks.

Old version of flipsky 6354 190kv on the label (actually just around 160kv upon testing). That indirect seller is unreliable. Even if flipsky have replacements, shipping em to my location would cost as much as the motor itself. I’m already committed to diy the shaft replacement.

If ur in the US Banggood has some replacement motors u can get in a week. Btw they have the non battle hardened and battle hardened variants. Comes from a wharehouse in Cali.

Aluminium doesn’t get red hot so do not try to use this as a temperature indicator.

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The broken shaft came off after a careful hammerjob. Thanks to @Mikeyrides for the reference.

Bought 1’ x 8mm stainless shafting rod from a local hardware shop. Cost me only an equivalent of 0.8USD.

Cut the shaft to slightly longer than the original. Figured out that the replacement shaft is several micrometers bigger in diameter compared to the original. Could not pass though the bearings as is. After some fine sanding and another session of careful hammerjob the replacement shaft finally set into place.

Lock rings are for pusseh! and did what @trelensis suggested. Thanks a lot dude.


Did some bench test. Actual ride test will come after the threadlocker fully cured.

btw, as I was tryin to remount the motor I noticed that the motor mount is slightly bent. Turns out this is a case of chain-sprocket disalignment after all. For the first time I dun feel so secured riding on a chain drive.
Yet another session of hammerjob took place to straighten the mount. Probably not a good idea to reuse a repaired malfunctioning mount…

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I thought once the magnets cooled back down, they’d be back to normal in terms of magnetization? Or does that only happen up to a certain temp? Or is it some other property that gets damaged?

you could loose magnetism due to excesive heat, and you would not get the same magnet spects after damage is done…but if you have no choice, use the force or heat, or you will spend some time waiting for a replacement…also, a broken magnet could be glue back together, not the same to loosen magnetism (which it woulb be a dramatic failure)

If a magnet breaks, the other part becomes a different polarized entity and can not be glued together anymore.

nope, I have a maytech, all destroyed magnets, and glued the back with battle harden the can and peaces of magnets again with epoxy…my wife use it for years…and i am not the only one in the forum who went thru the same situation

:+1: i could be wrong ofcourse, but most likely your motor would run without a magnet there :thinking: