Kingsong S20/S22 (Confirmed)

[litewave]

1 hour ago, Robse said:

hmmn.....  

 

What is the sample size for each wheel? The graph and counts mean nothing unless they are normalized to the same scale.

[techyiam]

On 11/5/2022 at 3:07 PM, Tawpie said:

It arrived today... going through pre-launch procedures.

When you placed your order for your S22, did you have to choose a motor option right there and then?

[Robse]

43 minutes ago, litewave said:

 

What is the sample size for each wheel? The graph and counts mean nothing unless they are normalized to the same scale.

it was just a joke :-) based on the pages pr. wheel.

[Paul A]

From the S22 motor stator slippage thread:

 

1 hour ago, sunstrong said:

I just placed an order. The options they gave me:

1. They'll send the motor to RevRides to get it pinned (for free)

2. Wait for the new batch from Kingsong to arrive (may be Dec, Jan) and replace the motor.

Two options are mutually exclusive, if I choose to get it pinned they won't offer the new motor for free. So I chose No.2 (I guess it's placing a lot of hope on the next batch of motor to fully solve the issue)

[Tawpie]

2 hours ago, techyiam said:

When you placed your order for your S22, did you have to choose a motor option right there and then?

no, I didn't see any option to choose and option. If there is an option, I'll probably wait though… pinning seems to me like it's a patch. One that probably works just fine, but a patch none the less.

[techyiam]

13 minutes ago, Tawpie said:

no, I didn't see any option to choose and option. If there is an option, I'll probably wait though… pinning seems to me like it's a patch. One that probably works just fine, but a patch none the less.

That was what I was suspecting since you didn't mention it before. So, this is new, and it makes a lot of sense. This would minimize motor damage, and save on shipping, for the case when the pinning option is chosen. Thanks.

[Rawnei]

26 minutes ago, Tawpie said:

no, I didn't see any option to choose and option. If there is an option, I'll probably wait though… pinning seems to me like it's a patch. One that probably works just fine, but a patch none the less.

That's exactly what the replacement motors is, pinned in factory.

[Rollin-on-1]

6 hours ago, Paul A said:

survivorship bias

I LOL'ed 

[techyiam]

59 minutes ago, Rawnei said:

That's exactly what the replacement motors is, pinned in factory.

Are you sure? How do you know that it won't be a motor of a different brand?

[Rawnei]

6 minutes ago, techyiam said:

Are you sure? How do you know that it won't be a motor of a different brand?

All current motors are pinned ZX motors. ZX started pinning them in June. There is a rumor that KS is switching motor supplier but no concrete info who and when. If someone gets a replacement motor in December means it was made in september or October. My own replacement motor as well as @supercurio replacement motor was manufactured in September.

[kiitick]

So here's a kind of a weird question.  I stripped the bushings on suspension when putting them back in.  I can't get them out, but I do want to replace them, even if I have to drill the suckers out of there.  Anyone have any idea what size they are/where I can order about 10 sets in case I strip them again?

[Tawpie]

2 hours ago, Rawnei said:

That's exactly what the replacement motors is, pinned in factory.

I'm certain it's a typo and they mixed up T4 replacement motors with S22... but the website did say the S22 'replacement' motor would be 'CS'. It was an error and I wasn't counting on that but I chuckled. Although I hear KS is switching vendors, so lord only knows.

Even though I consider pinning to be a patch, it's probably fine. Factory pinned could be better or worse, you don't want Al shavings wandering around in there. I'd guess RevRides would be very particular about that, but can only hope that ZX would exercise the same level of care... after you do a few motors you either get very good or careless (this is one of the reasons I consider it a patch—it doesn't take much lack of attention to end up with a hidden problem that's introduced by the rework)

[techyiam]

2 hours ago, Rawnei said:

All current motors are pinned ZX motors. ZX started pinning them in June. There is a rumor that KS is switching motor supplier but no concrete info who and when. If someone gets a replacement motor in December means it was made in september or October. My own replacement motor as well as @supercurio replacement motor was manufactured in 

I see. But you are speaking from what you know from the perspective of an owner, and someone who is not connected to a dealer or distributor.

I also understand that @supercurio has started a group that involves dealers and Kingsong. 

EEVEES and another dealer have both officially stated that they are expecting to get a different branded motors from Kingsong. 

My question is how sure are you that these dealers do not have more up to date and accurate information than you?

I guess what comes down to is do you or supercurio have better Intel than the dealers/distributors? 

EDIT:

The plot thickens. 

I just gone back to the EEVEES website. They have revised their statement from QS motors to upgraded motors.

Holy moly, you may be right after all.

Edited November 10, 2022 by techyiam

[fbhb]

2 hours ago, Tawpie said:

I'd guess RevRides would be very particular about that, but can only hope that ZX would exercise the same level of care...

@Tawpie, did you Not see how well the Rev Rides option of pinning is carried out? They have a professional engineering shop doing the work via CNC, so the attention to detail is exemplary.

This is in No Way "a patch", this is how it should be carried out to fix the issue and as @Rawnei stated is how we are told ZX have been doing so, however, I would be way more confident in having Rev Rides do the work than relying on the suspect reliability of the Chinese factory that stuffed up the tolerances in the first place!

Check out this video posted by Rev Rides on how to implement the pinning method and do so correctly:

 

Edited November 10, 2022 by fbhb

[techyiam]

@Rawnei

@supercurio

Are there any known cases of pinned ZX motors failing? 

[Paul A]

So why is it that other motors do not have the same issue?

If other motors do not have pins......then pins are a patch? and not the optimal option?

 

To salvage losses with a $50 fix?  Fails after the warranty period?

Are the pins going to fail/break from metal fatigue in a few months/years?

Seems like a lot of force borne by just four small pins.

Yes, metal shavings concern.

Edited November 10, 2022 by Paul A

[techyiam]

On that note, one has to ponder whether the S22 ZX motors will be all pinned going forward. In other words, ZX will not be fixing its design flaw in the near or foreseeable future for the S22.

This is not so hard to believe, in light of a company like even Begode felt compelled to jump ship.

Also, the Sherman-S motor, incidentally, also has an aluminum alloy hub that the stator ring assembly is bonded to. However, note that this motor is not pinned, but its stator ring has a much beefier and thick plastic structure, as shown in EEVEES Tear Down video of the Sherman-S. 

[Tawpie]

2 hours ago, fbhb said:

@Tawpie, did you Not see how well the Rev Rides option of pinning is carried out? They have a professional engineering shop doing the work via CNC, so the attention to detail is exemplary

I did see that! Yep, it looks like as good a way to do the rework as you could ask for.

Still... the root cause of the problem is probably a tolerance or materials issue and in order to address that you're adding a set of round pins that will transfer the force that would have slipped the stator vertically into the laminations that hold the coils. When the stator wants to slip (remember, you didn't correct the tolerance or materials issue so it still wants to slip), the lamination ring will want to ride over those pins and will want to deform the ring inwards. If it deforms the ring enough, it'll still slip (never mind that the coil alignment will be borked). If it doesn't, it'll put repetitive stress on the area around the pins—something that is unlikely to have been anticipated in the original ring design. What happens as a consequence, I have no idea. I don't know how slip prone these really are. I don't know what the ring is made of or how it might react to trying to ride over a pin. I don't know if the little divot in the lamination will get larger from wear. Heck, I don't know how the stator was expected to stay in place on the hub in the first place. I don't know a lot of things about it but pinning is adding a measure to compensate for a tolerance or material issue—and I don't know if the side effects of the cure are any better than the disease.

NEVERTHELESS.

The tolerance/materials at the root of this are very close to being adequate. It's not very far off. Pinning probably does provide sufficient margin to make up for inadequacies in the present design/manufacture. I'm not saying pinning is a priori evil, but I'd prefer a motor that doesn't need it or has it included as part of its design. RevRides probably has a better chance of getting the rework right than ZX—but ZX is also in a position to come up with a solution that addresses the actual root cause.

The replacement motors won't be in Canada for 1-2 months, they're probably leaving the factory about now. I'm hoping that they're not all reworked slippy stators, I'm also quite sure the majority will be reworked slippy stators.

Maybe, just maybe, ZX figured out what was really wrong in the late spring and the motors they're loading into containers now are actually 'better' than the ones that are getting round pins to increase their reliability. If you are going to key the stator, I'd like to see keystone pins with straight sides in there. Not holding my breath, but like I said… the pinning may be an adequate fix. They weren't that far from having it right from the get go so it shouldn't take much.

Edited November 10, 2022 by Tawpie

[Paul A]

The pins (positioning of holes drilled) seem to be orthogonal to the direction of forces...

 

ZX are the motor manufacturers?  And even Begode has abandoned using them?

[fbhb]

3 hours ago, Tawpie said:

The tolerance/materials at the root of this are very close to being adequate. It's not very far off. Pinning probably does provide sufficient margin to make up for inadequacies in the present design/manufacture. I'm not saying pinning is a priori evil, but I'd prefer a motor that doesn't need it or has it included as part of its design. RevRides probably has a better chance of getting the rework right than ZX—but ZX is also in a position to come up with a solution that addresses the actual root cause.

The replacement motors won't be in Canada for 1-2 months, they're probably leaving the factory about now. I'm hoping that they're not all reworked slippy stators, I'm also quite sure the majority will be reworked slippy stators.

Maybe, just maybe, ZX figured out what was really wrong in the late spring and the motors they're loading into containers now are actually 'better' than the ones that need pins to increase their reliability. If you are going to key the stator, I'd like to see keystone pins with straight sides in there. Not holding my breath, but like I said… the pinning may be an adequate fix. They weren't that far from having it right from the get go so it shouldn't take much.

I do take on board everything you stated here in "quotes", but my main point was to mention that "sloppy/wildly varying tolerances" between the 2 dissimilar metals, steel and aluminium (Oooh how many times have we heard that phrase before?) are the cause of the issue, along with the usual poor QC!

This is where we are now and a solution needs to address the problem of the initially discovered varying tolerances and unfortunately ONLY pinning of the existing ZX motors will be the chosen option, be it motors already out there or motors produced by ZX since the issue was discovered back in approximately June of this year.

@supercurio  with his engineer contact at King Song has clarified that point, but there has been NO word on a change over to a New more reliable motor manufacturer at this stage, the ONLY sure-fire way to have the S22 motor possibly not needing pins!

I see you mention that you hope they will not be "reworked slippy stators", whereas in reality they can ONLY be reworked motors if coming out of the ZX factory with NO guarantee they will have done anything to address the tolerances. This is why I personally would put a Rev Rides pinned motor (especially when you can see exactly how the process has been carried out) way ahead of a replacement ZX pinned motor!

From an engineering point of view, the method of pinning cylinders, some with far greater load bearing demands, in this very manner is a very long-standing practice obviously along with keyways and tapered locking/interference fit keys. Usually ONLY one suitably sized set screw/pin is drilled and tapped or drilled for an interference/shrink/glued fit to secure an interference fit sleeve or bush as required, whereas we are using 4 here and some may actually call it overkill!

The load necessary for the stator to still turn once 4 pins have been correctly fitted far exceeds what we are likely to subject our S22's to - it is also of great interest that even Shibby although blowing multiple boards from his huge jumps, has reportedly NOT had the stator slip issue on his "unpinned" S22 motor!

Edited November 10, 2022 by fbhb

[Tawpie]

10 minutes ago, Paul A said:

And even Begode has abandoned using them?

They used them in the T4 and suffered the same stator slip problem and BG is now shipping CS motors as replacements. We don't know exactly 'why' BG changed—slippage had to play a part but we don't know the full story and I'm guessing that slippage was the proverbial straw.

[Rawnei]

5 hours ago, techyiam said:

I see. But you are speaking from what you know from the perspective of an owner, and someone who is not connected to a dealer or distributor.

I also understand that @supercurio has started a group that involves dealers and Kingsong. 

EEVEES and another dealer have both officially stated that they are expecting to get a different branded motors from Kingsong. 

My question is how sure are you that these dealers do not have more up to date and accurate information than you?

I guess what comes down to is do you or supercurio have better Intel than the dealers/distributors? 

EDIT:

The plot thickens. 

I just gone back to the EEVEES website. They have revised their statement from QS motors to upgraded motors.

Holy moly, you may be right after all.

Because I follow conversations on Telegram where various vendors and people connected to KS are and I also speak to @supercurio in real life who has direct contacts at KS, Eevees made a false assumption in this case and it's entirely possible that the other vendor who is also Canadian just followed along on that.

But pinning the motor is the fix for stator slipping, there is not so much more you could want in this case, a pinned motor = good motor.

5 hours ago, techyiam said:

@Rawnei

@supercurio

Are there any known cases of pinned ZX motors failing? 

No, it's believed to be a reliable fix.

[Rawnei]

3 hours ago, techyiam said:

On that note, one has to ponder whether the S22 ZX motors will be all pinned going forward. In other words, ZX will not be fixing its design flaw in the near or foreseeable future for the S22.

This is not so hard to believe, in light of a company like even Begode felt compelled to jump ship.

Also, the Sherman-S motor, incidentally, also has an aluminum alloy hub that the stator ring assembly is bonded to. However, note that this motor is not pinned, but its stator ring has a much beefier and thick plastic structure, as shown in EEVEES Tear Down video of the Sherman-S. 

The pinning fix was initially done by the russian EUC community, I wouldn't be surprised if it was KS who pushed ZX to start pinning them, I also imagine it takes time to switch motor supplier because of negotiations, preparing production etc so it doesn't happen overnight.

[techyiam]

3 hours ago, Rawnei said:

The pinning fix was initially done by the russian EUC community, I wouldn't be surprised if it was KS who pushed ZX to start pinning them, I also imagine it takes time to switch motor supplier because of negotiations, preparing production etc so it doesn't happen overnight.

Alienrides currently sells the T4's with the new QS motors.

Kevin at E-rides found fault with the S20 motor so many months ago when E-rides first received their first S20.

But even if this data point was disregarded, stator slippage issue on the S20/22 was widely known before it was widely known on the T4.

Begode drops ZX like a hot potato and switched to QS, which is a known motor manufacturer. It looks like Begode did not pursue the pinning route.

The turn around time for proper resolution between the two manufacturers is staggering.

 

Edited November 10, 2022 by techyiam

[techyiam]

2 hours ago, Rawnei said:

Because I follow conversations on Telegram where various vendors and people connected to KS are and I also speak to @supercurio in real life who has direct contacts at KS, Eevees made a false assumption in this case and it's entirely possible that the other vendor who is also Canadian just followed along on that.

Thanks for sharing this info.

The S22 has been on sale for some months now. What is puzzling is why wouldn't dealers themselves, like the fine folks at EEVEES, know how serious the stator slipping issue is? Why would they need to be told by someone who does not even work in the industry.

Is the failure rate a publically know stat? 

It almost seems like the dealers were not aware of the severity, and were told or warned by @supercurio about the severity of stator slippage issue. Shouldn't this be more of a thing between Kingsong and the dealers/distributors themselves who would have the statistical data, and the actual failed units to diagnose?