ICE CRUSHER | 16ply HOLYPRO | 4W chain drive MTB | 4x 6374 170kV APS | quad ESCAPE | Steering damper

Andy87 · December 27, 2018, 10:02am

Update the last ride in deep snow: snow

First impression of the MBS F5 bindings are super. Feel way much more locked with them. First impression of the MBS 9" wheels… they definitly rock da house… super good grip even on snow. didn´t expact that.

As usual not everything went well on by ride. I got suck once in deep snow and was wondering why. Realised that the XT90s on the back ESCape box became lose a bit and the VESCs throttled down the power output. The problem caused the very tight cable length and that I fixed the cable on the bindings. I´ll probably just add a adapter xt90 which will give me like 5cm more length and everything should work than in future without issues.

Unforunatelly that was not the only fault… Short after that I noticed some kind so scratch noice comming out of the front. Very quickly I realised that something with one of the motors went wrong, so I tried t come home as fast as possible. At home one motor already didn´t moved at all anymore, so I took the motor appart and found one borke magnet there… As this was the last opportunity for me to drive this year I decided to take the second board and continue driving… Eveything was fine for the first 15km… after that the same thing happened… so in total I broke two magnet on two motors and both of my boards… That´s not how i expacted the year to end. I can´t explain the broken magnets as they didn´t got hot etc. but I now definitly know that it happend while i had bad contact with the road and the wheels where spinning up on a high rpm.

If somebody can explain me what could cause the broken magnets I would be very happy.

That´s already the 3rd bell from this motors with this issue. I still worry a bit that this can happen one day when I drive on top speed… motor locks up and I, with bindings, locked to a 25kg board

So what´s my plans now… I´ll get two replacement bells for the broken two. That will happen only in January, so till middle of February my quad is definitly out of work I already started to battle harden the motors which still working. That means I fill the empty space between the magnets and the bell with epoxy. I hope that will give them more strengh and it was the last broken magent on this motors. Honestly I would like to swap the motors to maytech or similar after that experience, but to swap out 6 motors is not really a cheap thing and than you also don´t know if it will maybe happen with the new once too.

Here one picture how I get my boards dry after a snow ride double

And even if i hadn´t too much driving time, I tried to make some small videos

moon · December 27, 2018, 10:08am

Nice hat on the helmet

Andy87 · December 27, 2018, 10:23am

I ordered a full costume, but unfortunately that didn’t arrive in time… Something left for next year Christmas

Pedrodemio · December 30, 2018, 12:42am

That’s a shame, only a long shot, how cold was? The glue that holds the magnets could’ve become brittle and gave up

Andy87 · December 30, 2018, 1:14am

-6 round about. The glue looks perfect after I took off the bell. The only thing I can imagine that there was too less glue. There is a big difference in how magnets glued in on the 6374 compaired to the 6384. I really didn’t expect the 6373 to get lose magnets. I now added glue to all bells which where still working. Will need to update some pictures soon. If now still something break I really don’t know anymore.

Pedrodemio · December 30, 2018, 1:53am

If it turn out to be a problem, apparently @torqueboards motors doesn’t use glue at all to secure the magnets, only interference fit of the magnets and the retaining ring in the bell, never had problems, but also it never snows here

Andy87 · December 30, 2018, 2:17am

I thought abou the 6380 as option in case, but that would mean to buy 6 new motors and new pulleys and new sprockets as the APS motors have 10mm shaft and torque boards have 8mm

banjaxxed · December 30, 2018, 8:55am

Would the snow freezing the glue have an effect? Hard to tell if you were just unlucky.

Use fancy high/low temp epoxy to put the pieces back in, replacement magnets not sure where to source em, it would be cool to have replacements.

Looking good, can’t watch vid atm but looking forward to it later

Andy87 · December 30, 2018, 10:34am

I‘ll get new bells. APS has a very good customer service as far as i can say. But that will be only during January, than there is my vacation etc. So probably no ride till mid February

I don’t believe that the coldness can have a big influence. The motors are warm from home when I leave and they hold them self in a good 30-50degree range while riding. It’s also not like I through them into ice water when they 100 degree hot or so. In this case i could understand that the glue would go off.

totalgeek9224 · December 30, 2018, 10:49am

Although not necessarily that extreme of an example, thermal shock could be what caused it. As they heat up the metal expands and as they go through snow/ ice water they try to retract quickly, causing the brittle epoxy to break off

Andy87 · December 30, 2018, 10:55am

Sure that could be somehow a reason, but why exactly my motors. I mean i‘m not the only one driving at minus temperature and the motors where never super covered with snow. If I think about diffmans crazy Quad it was working flawless in the winter and he hit definitely more snow over the motors than me.

totalgeek9224 · December 30, 2018, 11:27am

I wish i had an answer for you, but alas. It could be an issue like maybe theyre using a new epoxy or somnething

Riako · December 30, 2018, 11:31am

hum, it could be. Like his crazy VESC (4.07?4.10? handled more than 125Amps …), I know he also custom his motor to redious the kV to around 130, he maybe custom the bells too …?

I haven’t notice any difference (noize or anything) except the range when riding around 0°C lat year (but they’re Overion low kv custom motor with the closed bell, I know as Torqueboard he ask almost all component and composite custom and more control stage than the standard enclosed motor made by Maytech as we could find at many shops):

I’m really interested if you have some photo of the inside after your custom epoxy work ? I would do the same to prevent any fail on my futur diy hub motor

Duffman · December 30, 2018, 12:47pm

I read about this problem several times, but only on APS motors. It seems, that they had or have a problem with their glue or glueing process. Jenso broke 4 APS motors within a few days. I tried to fix them: broke all magnets out, cleaned them, cleaned the bell and glued them back in. I tried this several times with different glues but had no luck. They always came loose again.

I hope you have better luck with yours, but you should maybe lower your motor amps until you get your replacement bells.

Andy87 · December 30, 2018, 2:01pm

I‘ll upload some pictures after my New Years vacation which started today

Andy87 · December 30, 2018, 2:08pm

That’s I interesting to hear. Thx for your input, very much appreciate that. I had a small talk with bruno from aps and he said that they had this issue before but solved it on newer motors by applying more or different glue. But he also said that that should have been on the motors I have. However, I noticed a big difference in how the magnets on the 6374 motors glued in, compaired to the 6384. on the 6374 motors you can der that there is some epoxy or other glue even around the magnets. On the 84 motors that’s not the case. I wonder why especially the APS motors have that. If you say you tried different glues it maybe could be the material they use on the bells. Maybe the metal part expand faster or something like this and with it the epoxy get lose from the magnets or can’t hold the magnets anymore.

FredrikHems · December 30, 2018, 3:12pm

Have anyone tried using green loctite to glue the magnets back in? My guess is that the loctite should be strong enough to keep the magnets in place, however the heat of the motors might be an issue…

Andy87 · December 30, 2018, 4:02pm

As far as I know @Kug3lis used green loctite to glue his magnets back in on the 6384 motors. As my magnets already totally broken I can’t glue them back with loctite. Honestly I applied some green loctite inbetween of the magnets in hope it will fill out some parts which maybe not glued properly. Buuut as we can see that didn’t do the job in my case.

Andy87 · January 16, 2019, 6:45am

Last update was that I broke some magnets in some of my motors. That´s why I decided to “battle harden” the bells of all the still working motors. I´m very tired from this picture: It´s already the third motor and this way is my last hope to get this motors work more reliable. But what is battle harden? Battle harden means to fill all gaps in the motor with epoxy. this way the magnets are more strong fixed and should withstand even an impact. It´s mainly used for fight robotic stuff. What do you need?

Epoxy (maybe also some thickener for your epoxy)
some wooden sticks
heat shrink big enough to cover the motor shaft
cups for mixing
lots of papers
gloves if you want

How it works? If you too lazy to read through, watch this video:

In the description you will also find some product information. As I sourced all my stuff locally I´ll not link anything. The epoxy I use is a 4min epoxy used for motor and car stuff. For me it has the perfect consistence. It´s fluent but still thick enough to don´t run away from the holes.

First you need to take appart the bell from the stator. Than you want to remove the shaft. As this might be not comfortable for most of us, you can just cover the shaft with heat schrink in the right size. You really don´t want to get some epoxy on the motor shaft. If you work on an old motor it makes sense to clean first the bell and make sure everything is dry before you continue to apply the epoxy. Depending on how fast your epoxy is getting dry and how fluent it is, you will need to mix up more or less epoxy. For me it worked best doing 3 lines than clean up everything, wait 3-4 min and continue with the next 3 lines. If you mixed up the epoxy you fill the space between the magnets with it. Probably your magnets will be covered with some epoxy too. Use the wooden sticks to clean the magnets as good as possible. Repeat this till all your magnets glued in and it looks like this or better

It´s recommended to let the bells sit like this as min one day. During this time I had a look at the stator too. Here you could do the same with all windings. It could probably help if you have a slightly lose winding or strange high pitch noice coming out of the motor at a specific speed. I for my own deceided that it´s not really necessary. One thing I didn’t like on the motors, that the phase wires are pressed to the housing. In this place the windings also soldered to the flex awg cable. I have seen pictures of broken/cut isolation exactly in this place, that´s why I decided to cover this place with epoxy too and restrict the cable moving to like zero.

If you do this too, take care that the phase wires are in the right angle coming out of the motor. If they stay up too much it´s not possible to mount your motor later

One more thing you could do in the same time, cover the sensors and pcb with some lack or epoxy too. waterproofing your hall sensors can save you from a lot of troubles.

Ok, so it´s time to put everything together again. Turn the bell with your hand and make sure nothing is rubbing. if it is, some 500 sandpaper can help to get rid of this.

I also recommend to do a new motor detection after you assembled everything back, to make sure everything works how it should.

Happy riding!

For now I could test the battle harden motors only on the bench. Still waiting for one replacement bell for the 6374 motors. If all this was worth the work will be reviewed in one of the next updates here.

@Riako finally made it to write everything down

totalgeek9224 · January 16, 2019, 7:17am

Definetly something I’ll wanna do when I start building, if it works its worth the hassle over the cost and time of a broken magnet

Good writeup!!