Hollow bore motor bearing failure Thread

[WheelyBad]

8 minutes ago, AtlasP said:

Why not MSP over MSX?--quite a bit newer/nicer while being just before the bearing issue introduced with the RS.

The MSP Torque was actually my first choice, but I had the same issue finding new stock with any kind of a warranty. I've never considered going to aliexpress, though, so I guess I kneecapped my search. Any thoughts about where I might pick one up would be greatly appreciated.

[StealthPhoenix]

ive resigned myself to accepting that this sound can only be caused by a loose magnet or coil.

it may seem sturdy when you open it, but unless we have clear motor covers to see how things function when everything is energized, i just cant buy into the bearing problem. a bearings purpose, is to achieve, allow, and maintain rotation, just like a wheel. in lieu of a trusted solution, everyone is brainstorming and though that is a great first step, it seems we are falling into the trap of making things more complex, because we think we have fully exhausted the simpler possibilities. i dont believe we have exhausted simpler possibilities. i ride mine everyday. and i love it. it performs. it goes up 13+% hills, it does well enough to keep me pleased without worry on offroad terrain. ive had the sound problem since like my 5th mile ever. i am now going on my 315th mile, riding at average speed of 18-24mph regularly, topping it out at least once each session around 33mph (though it can go more). a wheel with a bearing problem could not handle the way my wheel still does. 

ive been riding a skateboard for more than 15 years. not a longboard that cushions all the bumps and cracks, but a good old fashioned skateboard that also utilizes 2 bearings per wheel. meaning i feel everything. at any velocity, on every trick, at every height that i jumped onto, or down. ive rode those bearings in rain and snow under the wheels themselves grinded down to like 30mm, and the bearing shields would fall off and you had to push them back on until the next 5 minutes when youd have to do it again. the principles of the bearings are the same, the mechanics are the same. i do acknowledge there is a slight change in feeling when the skateboard bearings start to go, but those symptoms and sensations are NOTHING like this sound.

nor is it the shell or any of the components held inside it. i removed the shell, kept the pedal hangers on, tucked the motor cable into "the hollow" and wheeled the euc upright with both of my hands on each of the pedal hangers and the knocking sound was still there. when i remove the cover, you cannot turn the motor anymore because one side sticks to the magnets, (there is an uneven air gap), but the bearing itself RETAINS the rotating ability. the little dirt i show and how people are thinking you need to lubricate it and whatnot is just nonsense. even the handymen on this forum seem to be fooled. in fact, i think it is best that you NOT lubricate the outside of "the hollow" on which the bearing sits as i have seen in an otherwise excellent video), because only the INSIDE track of the bearing should be moving WHERE THE BALLS RESIDE. there shouldnt be any slippage on the outer surface of the bearing (it should actually lock together with whatever surface it is touching, to achieve a true mechanical energy transfer.

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i dont want to rant once again, and im sorry for this being so lengthy and wordy already. my bottom line stems from laziness and defeat:

i strongly believe that in MY situation (knocking sound - sporadic. more so on some days, some days not at all, wholly unpredictable, and no other problems whatsoever. i can ride at 2mph or 33 mph without issue), it is definitely not the bearing. it is not the components in either shell. it is not the cable (inside the motor cover, or outside). from the sensation, it just feels like its a loose magnet. but because the magnet could still be magnetized to the wall on opening, id only know if i keep opening the wheel up at each idea i get. and ive not sat down to jot down ALL THE POSSIBILITIES ever so i only open it one time. im too lazy to open it up each time, risking damage to the hardware, etc.

if anyone has the SAME issue as me, and nothing more, then if you really sit down and think about it, try to think in simpler terms, sometimes complexity causes more stress and drama, and im sure youll come to the same conclusion as me.

...im just wondering if i should continue riding it until one day that magnet just...breaks into pieces? or if i should contact ewheels and see what they say...or if i too should go the route of the sherman..or opt for like a nikola or something..

take care folks.

[StealthPhoenix]

37 minutes ago, pontoonpete said:

I just want to highlight that something needs to be fixed so that we get reliable high-quality wheels because electric unicycles are just so awesome!

thats it in a nutshell!

[Scottie888]

40 minutes ago, RagingGrandpa said:

Pay more, get more... MSX -> MSP -> Sherman, all good wheels.

Unless one can wait till all this hollow bore issues are solved (if they can be), it would seem like the old school bearing over axle geometry is the way to go. At least in terms of reliability. Now I'm no expert on motor/engine mechanics but this is the first time I've seen this type of design where the axle is independent of the motor bearings.

Is there other motorized applications that use this type of geometry?

[StealthPhoenix]

22 minutes ago, Scottie888 said:

Unless one can wait till all this hollow bore issues are solved (if they can be), it would seem like the old school bearing over axle geometry is the way to go. At least in terms of reliability. Now I'm no expert on motor/engine mechanics but this is the first time I've seen this type of design where the axle is independent of the motor bearings.

Is there other motorized applications that use this type of geometry?

..

both the axle..or the hollow, are independent of the bearings. they remain static (as you are standing on them anyway. but you can turn the axle or the hollow by hand, in which case the outside of the bearing remains static (as the tire is not turning)...or you can turn both the inside and outside of the bearing at varying degrees, which is bearing slippage..

the bearing depends on the axle..or the hollow, to provide the static point from which it can allow the motor to turn

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...these are BRUSHLESS DC MOTORS (BLDC MOTORS), like the ones used in drones and rc toys i believe

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nvm. i dont think my answer applies to ur question haha. sry

Edited January 7, 2021 by StealthPhoenix

[pontoonpete]

Here’s a link to a video that shows removing a large pin that is pressed into a bore. Recognized a popping sound or clicking sound? The clicking sound you hear when rotating your wheel is the bearing misaligned and shifting within the press fit part of the housing. The clicking or popping starts at around one minute and 45 seconds into the video. Make sure to watch the video underneath of the sound the RS is making. Two videos below.

https://www.facebook.com/100156965192353/videos/357474182243894

Edited January 8, 2021 by pontoonpete

[Scottie888]

3 minutes ago, StealthPhoenix said:

..

both the axle..or the hollow, are independent of the bearings.

LOLs I guess I'm not phrasing my thoughts correctly. What I meant is normal motors (combustion or otherwise) the drive axle is enclosed through the main motor bearing/s where the bearing also becomes part of the load bearing component due to its geometry kinda like a unibody where the frame is part of the structural support. 

In this hollow bore application, the bearings seems to be independent of stucture & load support which as @pontoonpete alluded, can introduce extraneous lateral forces other than the tradition axial. Am I wrong in this interpretation?

[tumbla.jr]

New bearings just arrived. Let the fun begin!

[StealthPhoenix]

35 minutes ago, Scottie888 said:

LOLs I guess I'm not phrasing my thoughts correctly. What I meant is normal motors (combustion or otherwise) the drive axle is enclosed through the main motor bearing/s where the bearing also becomes part of the load bearing component due to its geometry kinda like a unibody where the frame is part of the structural support. 

In this hollow bore application, the bearings seems to be independent of stucture & load support which as @pontoonpete alluded, can introduce extraneous lateral forces other than the tradition axial. Am I wrong in this interpretation?

oh man..too much bill nye shit going on here, my brain is fried. 

but i do agree with you: i think the bearing is independent of load support (the pedal hangers take all the load, and THEY are mounted to "the hollow" itself, not the bearing, or the motor cover. so all the weight is on the hollow axle, radially. and not at all on the bearing. the shell itself is mounted again to the pedal hangers. 

i have come to imagine this hollow design as simply analogous to a normal axle setup as in the old wheels, but an axle that has been "hollowed out." like a pipe being used instead of a solid metal piece (axle). everything else remains the same (if you dont get picky about scale regarding bearings and whatever). methinksthis

[StealthPhoenix]

19 minutes ago, tumbla.jr said:

New bearings just arrived. Let the fun begin!

did you get these bearings because you developed an intermittent knocking/clicking sound in your RS? assumption is"yes." but id rather not

 

[tumbla.jr]

Just now, StealthPhoenix said:

did you get these bearings because you developed an intermittent knocking/clicking sound in your RS? assumption is"yes." but id rather not

 

Beyond rusty with 240 miles on the clock. 

[StealthPhoenix]

59 minutes ago, pontoonpete said:

Here’s a link to a video that shows removing a large pin that is pressed into a bore. Recognized a popping sound or clicking sound? The clicking sound you hear when rotating your wheel is the bearing misaligned and shifting within the press fit part of the housing. The clicking or popping starts at around one minute and 45 seconds into the video. Make sure to watch the video underneath of the sound the RS is making. Two videos below.

https://www.facebook.com/100156965192353/videos/357474182243894

this is a video showing how rusted metal sounds being pulled out of another rusted metal. aka the PIN (akin to an axle, not a hollow "BORE" motor.), being pulled out of a hole. everytime you pull with enough force that the rust between the two metals (the outside of the pin being pulled out, and the inside of the hole that it sits in) can shift, the rust then begins to collect internally, until there is no more space for the rust to continue collecting, and it "explodes" internally, causing that noise, as well as enough "explosive force" to have cleared the collected rust internally and continue to allow the pulling force to do its job (you can note the rust dust everytime the sound is there, indicating the rust is being expelled. as further proof, the sound goes away entirely, near the end, while still being pulled out little by little, as all the rust near the end, was either never there on that portion of the pin, or has been removed enough so that it doesnt collect and explode as intensely.

but the sound is indeed compellingly similar!

[StealthPhoenix]

18 minutes ago, tumbla.jr said:

Beyond rusty with 240 miles on the clock. 

but do you have any knocking noises at all? like a rhythmic tock tock tock?

[tumbla.jr]

7 minutes ago, StealthPhoenix said:

but do you have any knocking noises at all? like a rhythmic tock tock tock?

No just constant grinding. 

[StealthPhoenix]

12 minutes ago, tumbla.jr said:

No just constant grinding. 

cool man. i hope the new bearings work out well....but do you ride in rain tho? ive got more than 300 miles on my RS and its only been like 3 weeks.

if i had to change bearings every 250 miles, id throw my euc in the trash resentfully

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edit: i want to note that you dont have any knocking sound, and your magnets look so much more closer (basically no gap at all) than the setups ive seen that have the knocking issue (including my own). if you have any more FULL view pictures of your exposed motor, specifically showing the entire circumference of the magnets and how close or far apart they are, that would prove worthwhile dude. 

Edited January 8, 2021 by StealthPhoenix

[tumbla.jr]

Not seeing any changes on the surface...

 

Edited January 8, 2021 by tumbla.jr

[tumbla.jr]

Just now, StealthPhoenix said:

cool man. i hope the new bearings work out well....but do you ride in rain tho? ive got more than 300 miles on my RS and its only been like 3 weeks.

if i had to change bearings every 250 miles, id throw my euc in the trash resentfully

No rain riding yet. Hopefully it’s not a reoccurring issue. 

[pontoonpete]

1 hour ago, StealthPhoenix said:

this is a video showing how rusted metal sounds being pulled out of another rusted metal. aka the PIN (akin to an axle, not a hollow "BORE" motor.), being pulled out of a hole. everytime you pull with enough force that the rust between the two metals (the outside of the pin being pulled out, and the inside of the hole that it sits in) can shift, the rust then begins to collect internally, until there is no more space for the rust to continue collecting, and it "explodes" internally, causing that noise, as well as enough "explosive force" to have cleared the collected rust internally and continue to allow the pulling force to do its job (you can note the rust dust everytime the sound is there, indicating the rust is being expelled. as further proof, the sound goes away entirely, near the end, while still being pulled out little by little, as all the rust near the end, was either never there on that portion of the pin, or has been removed enough so that it doesnt collect and explode as intensely.

but the sound is indeed compellingly similar!

Every bearing install is different. It's not unusual for brand new bushings or bearings making a popping sound while being pressed into place. I just don't have any recording of a new bearing/bushing making that sound. I'm a heavy duty mechanic and if you know any personally and you ask them about that sound they will agree with me. You are completely right in this instance though that the video does show a rusty old seized pin being pulled out. 

Edited January 8, 2021 by pontoonpete

[.....]

15 minutes ago, pontoonpete said:

Every bearing install is different. It's not unusual for brand new bushings or bearings making a popping sound while being pressed into place. I just don't have any Recording of a new bearing/bushing making that sound. I'm a heavy duty mechanic and if you know any personally and you ask them about that sound they will agree with me. You are completely right in this instance though that the video does show a rusty old seized pin being pulled out.

Yup, on the head. Creeeek, crik crik, pop! Then of course the obligatory clank clank, oh shit.. as the collection of shims and randomness on the press, falls to the floor endangering your feet. I can hear the sound now, it fills me with joy. Damn I miss my old overly dangerous and overly productive shop! My fav was when you use so much force that when it pops, you arent sure if its seated or exploded, and you're merely waiting for the blood to show up. I think the rust idea has merit, but this happens on clean parts too. Only a fool tries to press and install bearing races or bearings onto rusty and unprepared shafts/seats. Too bad we cant avoid it on removal most times. Elbow grease, heat, cooling and sandpaper are not magical tools of the wizards... If you dont completely destroy old parts on removal, they make perfect spacers to help install the new as well. Or at least its more stuff to fall on your feet next time..

Edited January 8, 2021 by ShanesPlanet

[tumbla.jr]

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.

[Flying W]

@tumbla.jr were your old ones using the metal covers, and do the new ones have rubber covers?

[tumbla.jr]

Just now, Flying W said:

@tumbla.jr were your old ones using the metal covers, and do the new ones have rubber covers?

Both are rubber. The old vs new look identical. 

[Flying W]

25 minutes ago, tumbla.jr said:

Both are rubber. The old vs new look identical. 

Hopefully your original ones where damaged on assembly and drank salt water all the way across the ocean. They look so rusted. 

I hope the new ones work out well! Mine has been fine, only 220 miles so far but it's been great. 

 

[tumbla.jr]

5 minutes ago, Flying W said:

Hopefully your original ones where damaged on assembly and drank salt water all the way across the ocean. They look so rusted. 

I hope the new ones work out well! Mine has been fine, only 220 miles so far but it's been great. 

 

Who knows. Wheel is back together and fine so far did a quick 30 mile shakedown. Time will tell...

Edited January 8, 2021 by tumbla.jr

[Planemo]

10 hours ago, Scottie888 said:

Now I'm no expert on motor/engine mechanics but this is the first time I've seen this type of design where the axle is independent of the motor bearings.

They're not independent. We established this a few posts back.

The design is in fact very similar to a 'conventional' axle setup. But with the RS, just imagine it's using a much larger diameter axle, but hollowed out.