Hollow bore motor bearing failure Thread

[StealthPhoenix]

11 hours ago, tumbla.jr said:

I’m not sure what happened to the one that failed but it’s completely discolored compared to the other one. Even the bearing grease is a diff color.

discoloration shouldnt be an issue. and different grease formulas are just colored different, sometimes theres no change in chemical composition, its just the brand trying to be "different." and the rust you show seems to have come from being too DRY, like the existing grease just...got used up and exposed the metal enough to develop rust, and could even be tiny particles of dirt and streetwater that just mixed with the grease and remained over time, eventually the water drying out and then rusting. you could clean it all out with some quality degreaser, or even alcohol....and then use a heavy duty grease similar in viscosity to the same grease or even experiment with slightly lower (more liquidy) or higher viscosity (thicker), keeping in mind the range of temperatures your euc hits (via the data from euc world, darknessbot etc). and coat the entire inside of the bearing (leave no exposed metal part that can rust, so lay it on thick enough that it seeps into all the little areas. this can be some periodic maintenance thing, every few hundred miles depending on how you ride and what you ride in)

but anyway, things to keep in mind if you feel experimental and curious on ur next turnaround.

Dr Jekyll & Mr Glyde 

[AtlasP]

9 hours ago, StealthPhoenix said:

this can be some periodic maintenance thing, every few hundred miles depending on how you ride and what you ride in

jesus, having to clean and replace bearing grease every few hundred miles (every week or couple weeks for some of us) sounds like a new rung of hell.

Edited January 8, 2021 by AtlasP

[Scottie888]

14 minutes ago, AtlasP said:

jesus, having to clean and replace bearing grease every few hundred miles (every week or couple weeks for some of us) sounds like a rung of hell.

Yup double Jeeeesus here!! Made me super happy I decided to hold on to the RS or EX upgrade til this whole mess settles. Just the thought of cleaning & repacking bearings every few hundred miles gives me the goosies, nevermind replacing them.

[StealthPhoenix]

16 minutes ago, AtlasP said:

jesus, having to clean and replace bearing grease every few hundred miles (every week or couple weeks for some of us) sounds like a rung of hell.

i feel the same with everyone touting "replace the bearings!" as optimal solution.

i just ride and charge. and thats my plan until i cant do either, for any reason. 

simple as that

 

[EUC Custom Power-Pads]

On 1/8/2021 at 3:16 PM, StealthPhoenix said:

and then use a heavy duty grease similar in viscosity to the same grease or even experiment with slightly lower (more liquidy) or higher viscosity (thicker), keeping in mind the range of temperatures your euc hits (via the data from euc world, darknessbot etc)

If I do not misunderstand anything here due to lack of English knowledge, then I would not give the slightest thing to your advice due to extreme lack of expertise from this statement at the latest.

After this statement, I would ignore all your posts with technical content.
Bearing grease viscosity determination based on a control board temperature.

Edited January 10, 2021 by buell47

[StealthPhoenix]

4 hours ago, buell47 said:

If I do not misunderstand anything here due to lack of English knowledge, then I would not give the slightest thing to your advice due to extreme lack of expertise from this statement at the latest.

After this statement, I would ignore all your posts with technical content.
Bearing grease viscosity determination based on a control board temperature.

LOL shit you are absolutely right dude. ive had the euc for about a month now, and im still discovering my way around it. i got distracted while brainstorming i think and just made a huge error there. im glad you caught it!

i think i developed tunnel vision in just thinking mechanically and began to to experiment (in my mind) in that area only.

@buell47 you may say your english is not good (which i think is false), but i appreciate your brain! 

[EUChristian]

1 hour ago, StealthPhoenix said:

LOL shit you are absolutely right dude. ive had the euc for about a month now, and im still discovering my way around it. i got distracted while brainstorming i think and just made a huge error there. im glad you caught it!

i think i developed tunnel vision in just thinking mechanically and began to to experiment (in my mind) in that area only.

@buell47 you may say your english is not good (which i think is false), but i appreciate your brain! 

All good - 👍

[pontoonpete]

Just replaced the bearings on my friends RST. Only one bearing was bad. Obviously replaced both. 

 

Upon close inspection, I could tell that the bearing that was failing was definitely not installed as easily as the other one during factory assembly. I noticed that there was significant marking in the housing where the outer race of the bearing is pressed into. Also, on the side that had the bad bearing the housing was cracked. My friend is sending in the pictures, we will see what happens. We installed the bearing in spite of the cracked housing. The crack is definitely not good for the longevity of the wheel but hopefully begode may send him a new motor or a new housing at the very least.

 

I question the quality of the casting as well. I could see a few tiny bubbles or porosity in the machined areas of the housing where the bearings are pressed into.

 

The bearing change went well. Disappointed with the overall quality but not surprised based on everything I've heard and read. 

[Planemo]

That crack is nasty. Not sure I could ride freely knowing that was there. Almost surely caused by pressing the bearing in at a slight angle or not heating the housing first and/or cooling the bearing.

Chinese pot metal is crap at the best of times, let alone when it's cracked. Be careful with that wheel...

[pontoonpete]

8 minutes ago, Planemo said:

That crack is nasty. Not sure I could ride freely knowing that was there. Almost surely caused by pressing the bearing in at a slight angle or not heating the housing first and/or cooling the bearing.

Chinese pot metal is crap at the best of times, let alone when it's cracked. Be careful with that wheel...

I agree! I'm hopeful he will get good a new housing in a timely manner at the very least. He will not be nailing any jumps in the meantime LOL

[Scottie888]

Wow that's crazy. I can't see how that bearing crack came about since the axle isn't attached to the bearing so there's no high stress vectors even on a heavy jump or other. Are my assumptions wrong here?

If they aren't, then either the bearings are crap or this new hollow bore thangy needs a complete redesign.

[Flying W]

@pontoonpete I know you said the damaged bearing showed signs of an improper install (I think Vee put a video up of gotway using a mallet haha) but did either bearing show signs of water damage? 

Now I want to pull my motor and check for cracks, I don't have any issues right now but I'd like to get that handled whil under warranty of there is any. 

Seems like every step forward had a step back with gotway right now...... but I'm loving the off road hill climbing on this wheel! 

[JirkaMak]

Hi everyone.

OMG, @pontoonpete, the crack is crazy. Fingers crossed for your friend, he should really get a new motor.

I have some interesting news towards the discussion about the bearings issue and the knocking sound. I can now say with confidence that if your problem is just the knocking sound and nothing else (nothing like the crack we saw one pontoonpete's pictures), the problem is very likely caused by the motor being misaligned as said by @StealthPhoenix.

He came with a solution, I tested it on my wheel, and despite it being probably a bit more complicated than in his case, or me being a poor mechanic (which I definitely am), I managed to fix my RS knocking sound without bearings swap. Yeah, you hear it right. I just removed the motor cover on the right side, aligned the motor as best as I could, closed it, opened the left side, did the same there, closed it, and the knocking is gone. At least for now.

I don't know how long it will stay, can not really ride the wheel outside now. I don't like icy roads and temp below 25F for riding. But it is possible to fix the wheel knocking without the hassle of bearings swap, if the tock-tock-tock sound is your only issue. Don't read me wrong, the root of the problem is till in poor quality of the parts and mediocre manufacturing process, but it's not caused by failed bearings.

All credits go to @StealthPhoenix, he helped me a lot in the process.

I already posted a video with the knocking being clear and sound, here is a short one after the fix. 

 

[Planemo]

I can't avert my eyes from the sandals 

[NordEstEuc]

hello guys, I have read about your solutions you and @StealtPhoenix and it would be important to know if the problem has been definitively solved, in this case let us know  unfortunatly my "tock" comes and goes randomly! 

Just to Know a wheel friend has found an interesting solution to the "dirt and the like" problem I post the link: https://www.facebook.com/100020450169922/videos/692036861487980/
is working on a final version

[JirkaMak]

6 hours ago, Planemo said:

I can't avert my eyes from the sandals 

I thought you'll like them. They are the best! Who would even think about the RS spinning on the background, right? 

The nature of the problem means that it could probably return on a crash, or possibly even if you hit a bigger pothole. The alignment is held by the friction between the cover and the rotor pushed together by the cover screws. Everything around it has a fair amount of play if loosened, so a good amount of impact G-s can probably shift it and cause the issue to return. I hesitated to tighten the screws hard. I don't have a torque wrench to control the force and the rotor is made from aluminium. I don't want to damage the thread. I'll let you know once I'll be able to take it out safely and ride it. There is like 14F outside right now, not gonna ride in that.

Make a great day everyone!

[StealthPhoenix]

On 1/17/2021 at 12:12 PM, NordEstEuc said:

hello guys, I have read about your solutions you and @StealtPhoenix and it would be important to know if the problem has been definitively solved, in this case let us know  unfortunatly my "tock" comes and goes randomly! 

Just to Know a wheel friend has found an interesting solution to the "dirt and the like" problem I post the link: https://www.facebook.com/100020450169922/videos/692036861487980/
is working on a final version

for me the noise is gone now for 300 miles

[EMA]

i'm facing knock issue on my EX, seems like the knock is caused by bearing not aligned still working on it, will post picture

Edited January 28, 2021 by EMA

[EMA]

After 1500km the knock sound started on my EX so I disassemble the motor to find out what’s happening:

As already described by @pontoonpete I can confirm that the sound is caused by a bearing moving into a misaligned motor, bearings are not hold in place but they can move laterally a bit.

In my case the side cover are not tight and don’t hold the bearing in place (the factory use something to hold them), on the left side I can even put and take out the bearing with my hands without heating the cover. I can move it with one hand…: https://www.dropbox.com/s/92pqfnn3taezi9y/bad side cover.mp4?dl=0

This problem is also amplified by some tolerance error in the bearing position, probably related to bad side cover. After closing the motor side the bearing is not completely in touch with the stator inside, I’ve 3d printed a tiny ring ( 0.4mm each side) to fit the gap.

With the spacing ring inserted in a good side cover the motor is centered even with only 1 bearing as you can see in the video: 

https://www.dropbox.com/s/pf8mzuicgj42b9x/cover_ok.mp4?dl=0

reference photos and videos here :

https://www.dropbox.com/sh/qgwx1mfok1osmfo/AACRCQSy8fY4ZJIjaWqqvfPka?dl=0

i've closed the motor and the knock is gone, it turns smooth and feel solid (it wasn't before), bearings seems fine, tomorrow i’ll seal the motor and try the wheel again

Edited January 29, 2021 by EMA

[EUC Custom Power-Pads]

I wonder why no one with these bearing problems rebuilds the bearings with this stuff. 

When bearings sit so loose is essential! 

[EMA]

8 hours ago, EUC Custom Power-Pads said:

I wonder why no one with these bearing problems rebuilds the bearings with this stuff. 

When bearings sit so loose is essential! 

Agree, the factory use something similar 👍

[EUC Custom Power-Pads]

You're probably talking about the guy with the hot glue gun, but that's not the right thing to do. 

[EMA]

50 minutes ago, EUC Custom Power-Pads said:

You're probably talking about the guy with the hot glue gun, but that's not the right thing to do. 

lol i get it now .... 

[StealthPhoenix]

11 hours ago, EUC Custom Power-Pads said:

I wonder why no one with these bearing problems rebuilds the bearings with this stuff. 

When bearings sit so loose is essential! 

ive been monitoring the various ideas everyone has been having regarding these problems...

but there is NO problem if you waterproof your euc BEFORE EVER going out to ride in rain or snow. jumps and stunts would be better if you exchanged with the shorter pedal hangers that increase height. for the knocking noise, i already posted solution

but the key thing is this: when you use the euc for things it was never advertised to be used for, especially the stock version, without any waterproofing treatment or modifications, then you should expect some negative result - your euc failing on you.

you are suggesting LOCTITE to hold the bearing on the cover and/or axle. 

i saw someone elses video where they are applying GREASE AND LUBRICATION to the axle where the bearing goes on

lol a new person would be perfectly confused who to follow, what to do

 

[Rawnei]

8 minutes ago, StealthPhoenix said:

but the key thing is this: when you use the euc for things it was never advertised to be used for, especially the stock version, without any waterproofing treatment or modifications, then you should expect some negative result - your euc failing on you.

The V11 is rated IP55 though so it should stand up to rain, obviously they didn't foresee the bearing problems.