King Song S22 motor stator slippage issue: more severe than expected

[Fonzerra]

On 9/25/2022 at 6:17 PM, pedroMDK said:

Afternoon! Is this the motor or the suspension making the popping noise? It doesn't sound clunky. I'm thinking suspension as I think I heard it make the pop when it was powered off. TIA for suggestions.

 

 

Hi pedroMDK,

Did you find out where the popping sound come from? This morning when i powered on mine, it popped just like in your video and it was when it stand still. I noticed it do the same popping when driving as in your video. I have just past 1000 km. with no issues, and now it does this popping :-(

[NErider]

Well, bad news, good news. I thought the S22 I received from Ewheels may have had the newest motor. But as per my request I was sent the wheel as originally made and I will be receiving a new motor when the shipment arrives. I had thought that due to a shipping delay, my wheel was held back for the update, but that was not the case. My fault for assuming. 

But, I stripped it down and did my best attempt at pinning the wheel myself. Which turned out OK, but not excellent. It is ba k together and works as intended. I feel I can trust it as is, but will definitely swap the motor when the new one arrives. 

[NErider]

Image of before the pin. I learned that the 'outer ring' that need to be pinned is partially into the location where the yellow plastic is. My first two holes I tried were centered and barely cut into the outer ring. 

This is the one shown above before the pin. You can see the line of the two layers here. 

[onkeldanuel]

4 hours ago, NErider said:

Image of before the pin. I learned that the 'outer ring' that need to be pinned is partially into the location where the yellow plastic is. My first two holes I tried were centered and barely cut into the outer ring. 

This is the one shown above before the pin. You can see the line of the two layers here. 

Which pins have you used here, any link? And how much in Total? I mean is it nescessary to pin only one side or both sides of the motor? (left and right side?)

[supercurio]

Another S22 landing stress test, this time with Zebastian, on a motor that already exhibited scraping sounds before - but these sound disappeared.
2400km+ wheel. This is the S22 we were taking as example in discussions to show that not all of them have problems. 

With this one we learned a few things:

• 15 landings in one spinning direction is entirely insufficient to check a motor health. The test KS validated is not valid.
• alternating landings spinning forward / backwards appear more effective to introduce slippage
• any scraping sound must be checked and likely indicate a faulty motor
• more tests needed to characterize the behavior.

With the drilling method becoming popular owners and dealers, prevention by adding pins in the motor is definitely a better strategy than breaking a motor. However if you're out of options: motor was made before July, dealer is not willing to replace the motor preemptively nor drill it and you can't do it yourself either, then definitely run this test.

[supercurio]

Watching the video one more time, it sounds like the drop #29 is different, possibly slippage here. https://youtu.be/s3cXe8TyyvQ?t=615

From the results of the two first tests, I would recommend:

• at least 30 landings
• try one of these sequence:
  (3x forward, 7x backward) x 3
  (1x forward, 1x backwards) x 15
  (1x forward, 2x backwards) x 10
  (1x forward, 4x backwards) x 5
• every landing must happen at full rotation speed

Either way, it's likely an imperfect result.

[Rawnei]

29 minutes ago, supercurio said:

Watching the video one more time, it sounds like the drop #29 is different, possibly slippage here. https://youtu.be/s3cXe8TyyvQ?t=615

From the results of the two first tests, I would recommend:

• at least 30 landings
• try one of these sequence:
  (3x forward, 7x backward) x 3
  (1x forward, 1x backwards) x 15
  (1x forward, 2x backwards) x 10
  (1x forward, 4x backwards) x 5
• every landing must happen at full rotation speed

Either way, it's likely an imperfect result.

Very difficult to execute this test perfectly, it's like you have to execute it until stator either slips or you give up and hope for the best, not very reliable!

[supercurio]

@Rawnei exactly, same as the V12 stress test: hard to execute perfectly, hardly conclusive.
A properly designed stress test would need to evaluate forces which are significantly greater than those met in real world usage, and we can't do that here - being limited by the controller's output.

One thing it's effective at is to guarantee a replacement motor after failing the test, as long as King Song replaces only motors which are already broken instead of offering a complete recall.
In all cases, swapping preemptively or adding pins before failure is a better solution.

[Eucner]

15 hours ago, NErider said:

Image of before the pin. I learned that the 'outer ring' that need to be pinned is partially into the location where the yellow plastic is. My first two holes I tried were centered and barely cut into the outer ring. 

This is the one shown above before the pin. You can see the line of the two layers here. 

KS has fixed motors with 4 pcs of 5 mm diameter pins going through the rim. I would drill the hole to the rim where it meets spokes. It is the thickest part of thin inner rim. The pin needs to have a tight fit and some glue. There is 10 spokes. Using 5 pcs of 4 mm diameter pins would be even better. Radius wise your hole is in a perfect spot.

Edited October 18, 2022 by Eucner

[NErider]

11 hours ago, onkeldanuel said:

Which pins have you used here, any link? And how much in Total? I mean is it nescessary to pin only one side or both sides of the motor? (left and right side?)

I installed 3 pins in total. What I did was use a spring loaded center punch, and a brand new high quality cobalt drill bit. Size 3/16"

 I only had drilling  access from one side due to the windings and the black plastic covers. So I drilled more than halfway  deep thru the stator-being very careful not to go all the way thru and destroy the windings.

I then used a piece 3/16" steel round stock rod.  Slid it into the hole and marked the rod at the edge. Then pulled it out and cut it with a hack saw. 

The fitment was pretty good but I could have used a drill bit just a bit smaller since it oversized due to drilling by hand with no fixture. 

Because of that, I chose not to use loctite bearing retaining compound and instead glued the pins in place with a combination of superglue, and Q bond. Which is essentially baking soda. 

The hole and pin were coated in superglue, I dropped in the pin and seated it with a hammer and punch. Let it set up a bit. Then topped it with the Q bond powder to fill any gap and bring it up flush. 

I feel if done properly even 2 pins from one side would be sufficient. It's not like the pins will ever shear, or the hub will deform over them. But with 4 proper pins by the Manufacturer, would be guaranteed to be solid. 

And my 2 other holes not pictured were right on the thick part of the spokes. This hole was not on the spoke as I tried to space them evenly. Really, spacing isn't too critical. I would do it in the spoke area if I had to do it again. 

[onkeldanuel]

16 minutes ago, NErider said:

I installed 3 pins in total. What I did was use a spring loaded center punch, and a brand new high quality cobalt drill bit. Size 3/16"

 I only had drilling  access from one side due to the windings and the black plastic covers. So I drilled more than halfway  deep thru the stator-being very careful not to go all the way thru and destroy the windings.

I then used a piece 3/16" steel round stock rod.  Slid it into the hole and marked the rod at the edge. Then pulled it out and cut it with a hack saw. 

The fitment was pretty good but I could have used a drill bit just a bit smaller since it oversized due to drilling by hand with no fixture. 

Because of that, I chose not to use loctite bearing retaining compound and instead glued the pins in place with a combination of superglue, and Q bond. Which is essentially baking soda. 

The hole and pin were coated in superglue, I dropped in the pin and seated it with a hammer and punch. Let it set up a bit. Then topped it with the Q bond powder to fill any gap and bring it up flush. 

I feel if done properly even 2 pins from one side would be sufficient. It's not like the pins will ever shear, or the hub will deform over them. But with 4 proper pins by the Manufacturer, would be guaranteed to be solid. 

And my 2 other holes not pictured were right on the thick part of the spokes. This hole was not on the spoke as I tried to space them evenly. Really, spacing isn't too critical. I would do it in the spoke area if I had to do it again. 

Wow, thx for your Explanation! Apreciate

Edited October 18, 2022 by onkeldanuel

[onkeldanuel]

On 10/18/2022 at 6:41 PM, NErider said:

only had drilling  access from one side due to the windings and the black plastic covers. So I drilled more than halfway  deep thru the stator-being very careful not to go all the way thru and destroy the windings.

I then used a piece 3/16" steel round stock rod.  Slid it into the hole and marked the rod at the edge. Then pulled it out and cut it with a hack saw. 

And how long should the pins be then? 

[NErider]

On 10/21/2022 at 2:42 AM, onkeldanuel said:

And how long should the pins be then? 

I did not specifically measure the pins. The were approximately 1" or a little longer. I basically drilled "most" of the way thru the stator but left a safe amount left that I absolutely would not come out the other side. If you drilled all the way thru, you would most likely drill thru the windings on the other side and destroy the motor.

To summarize a bit, this is a press fit assembly,  except it's a poor press fit, and the surfaces are probably rough in between the two layers. So any amount of pinning that won't deform (such as any steel pin) will pretty much guarantee that they can't slip anymore. Having two or more just helps in case there is slop when you drill and glue or lock tite the pins in. 

 

Since pinning my motor, I have full confidence that it won't slip and fail catastrophicly. But, I'll still swap the new motor whenever it arrives. This definitely works for now tho. 

One of the MOST important parts that I didn't mention is you must be 100% clean when drilling so no shavings stay in the motor or stick to the magnet. I used a bunch of tape to cover everything. And even then I had a vacuum and a small tube to suck out any possible shavings. 

[MetricUSA]

Here in Aliens Rides Response... 

https://alienrides.com/pages/king-song-s22-stator-slippage-motor-replacement

 

 

[techyiam]

2 hours ago, MetricUSA said:

Here in Aliens Rides Response... 

Kudos to Alien Rides. That would be expensive: free new motor, free replacement labor, and free return shipping for motor, with no support from Kingsong. 

[Driftcycle]

13 hours ago, techyiam said:

Kudos to Alien Rides. That would be expensive: free new motor, free replacement labor, and free return shipping for motor, with no support from Kingsong. 

 

Kingsong S22 Motor

These are definitely not cheap if replacing several customers, however is Alienrides replacing with the updated ZX motors with pin already installed? or the new motors from the manufacturer that Kingsong is rumored to have switched to?

[techyiam]

3 minutes ago, Driftcycle said:

is Alienrides replacing with the updated ZX motors with pin already installed? or the new motors from the manufacturer that Kingsong is rumored to have switched to?

According to Alien Rides website, the customer will be getting the new QS motor, unless the customer insists on getting his or her current motor pinned.

[Driftcycle]

1 minute ago, techyiam said:

According to Alien Rides website, the customer will be getting the new QS motor, unless the customer insists on getting his or her current motor pinned.

 

Nice - that's great  

[supercurio]

56 minutes ago, Driftcycle said:

Kingsong S22 Motor

These are definitely not cheap if replacing several customers, however is Alienrides replacing with the updated ZX motors with pin already installed? or the new motors from the manufacturer that Kingsong is rumored to have switched to?

Fortunately, while I don't know the price for a replacement motor AlienRides pays, it's nowhere near that (including shipping)
Some fat margins here...

51 minutes ago, techyiam said:

According to Alien Rides website, the customer will be getting the new QS motor, unless the customer insists on getting his or her current motor pinned.

QS motors are for the T4. The S22 "V2" motor are made by another factory but it's still unspecified which. Unlikely that these will be the replacement motors for Alien Rides.

Edited October 27, 2022 by supercurio

[Driftcycle]

53 minutes ago, supercurio said:

QS motors are for the T4. The S22 "V2" motor are made by another factory but it's still unspecified which. Unlikely that these will be the replacement motors for Alien Rides.

I'm guessing these new motors will debut in the anniversary edition first.

Have you heard any updates on timetable for the gold edition.

I assume they wish to launch in '22 during their anniversary year. As it will be odd launching an anniversary product outside that window. 

[supercurio]

2 hours ago, Driftcycle said:

I'm guessing these new motors will debut in the anniversary edition first.
Have you heard any updates on timetable for the gold edition.

Or possibly when they run out of ZX motors. Hard to tell.

I'm not paying attention to timetable, but I'm still concerned about some component choices for this "upgraded" mainboard. It's difficult to have a discussion on that with King Song so far, hopefully that can be solved without having to escalate this to the public.

 

On the other front, here's a super cool video from REV Rides showing how they're drilling S22 motors to address the issue!
Awesome 😄
This video serves both as marketing material for them as well as knowledge sharing with others interested in doing the same - dealers or owners alike.

When I see this, I'm super happy with the progress so far since the beginning, despite all the difficulties.

 

Edited October 27, 2022 by supercurio

[Driftcycle]

   Nice - pretty soon every dealer shop will need to be affiliated with a manufacturing arm to remedy the QC issues that will continue for some time, as the Imotion CEO said they have to continue ordering assembly parts from smaller plants because the larger ones with more quality require a minimum order that eclipse the EUC market. 

 

I see this as an opportunity for dealers to leverage their manufacturing affiliate and stand out by offering their own fabricated upgrades beyond the fixes as a selling point 

[RoboFixIt]

3 hours ago, supercurio said:

On the other front, here's a super cool video from REV Rides showing how they're drilling S22 motors to address the issue!

What REV Rides is doing with upgrading the s22 motors is really amazing and I don't think any other dealer is doing something this! I'm totally going to buy wheels from them!

[NErider]

Just my 2 cents. Ewheels also appears to be replacing many if not all affected S22 motors, and I personally pinned my own wheel motor sitting on my living room floor in my underwear with a vodka lemonade,  a drill, and a hack saw.  This isn't rocket science,  it's drilling a few  holes and lock tighting or gluing a piece of metal in it. Assembly is the reverse of removal. 

Should anyone HAVE to do this? Of course not, but 1st batch buyers should always be aware of these unfortunate, but blatantly likely type of repairs to this type of product. It's not like it hasn't happened over and over again.

[techyiam]

6 hours ago, supercurio said:

On the other front, here's a super cool video from REV Rides showing how they're drilling S22 motors to address the issue!

Wow, very impressive work. Notice indirectly, the chosen amount of interference via the light hammering of the pin, it was carefully considered. The stator coils are embedded in a plastic ring, and the metal pin is sandwiched between the plastic stator ring, and the aluminum alloy hub, but the plastic ring is on the outside, at a large radius. Since, it is an interference fit, the tensile hoop stress in the plastic stator ring could become too high if careful consideration wasn't given to the amount of interference. And of course the tight control of the tolerances. 

And don't forget they pulled out the stator first before drilling. That's a lot of work.

Edited October 28, 2022 by techyiam