Kingsong S20/S22 (Confirmed)

[supercurio]

7 hours ago, UniMe said:

Does anyone have a thought on the hall sensor redundancy and if this may have something to do with the wheel being slow off the line?

I'm wondering if this transition from the old to new hall sensor can only occur under certain motor loads, or below a certain speed. Or, if the older hall sensor responsible for starting the wheel up is somehow under performing...?

Understandable question, since a few influencers had various claims regarding the sensorless backup capability, including very confidently describing in a video that the motor had a "hall-less hall sensor" "does create a different feel to the motor in terms of how it reacts" and it "definitely isn't the exact same feeling as a true hall sensor motor" 

 

To answer the question, in my current understanding I guess we'll always have hall sensor in EUC motors.

The reason is that on an EUC you need extremely fine motor control even when it's not rotating in order for the self balancing algorithm to be smooth and stable. With a controller which has a hall sensor, you can get the full stall torque at 0 rpm.

When sensorless, the motor has to rotate at least a little bit in one direction or another for the controller to identify the right control sequence. On my e-scooter with basic squarewave controller, the rear wheel often tendency rotate first in the wrong direction at startup before correcting itself. It's very noticeable if the scooter is lifted and the motors spin in the air.
I read that the same thing can happen with VESC 6 which has much more advanced motor control algorithms.

Once a motor rotates tho, there's no difference in power delivery for the controller, regardless if it tracks the position of the motor from the hall sensor or back-EMF sensing.

In short, the speculation and claims regarding the sensorless backup and how it would affect either power delivery or feel are baseless.

My best guess on all this are:

• many riders are used to wheels with fewer protections, that will happily draw excessive current from the packs for the cells' health or cause the board to self-destruct if stressed enough instead of beeping and applying current limits.
• KingSong might not have finished tuning the motor and controller limits (based on cryptic Chinese translation: might not change compared to now)
• the description of current limit within the first 3 meters, in order to avoid boards burning - which was communicated to testers by KS is very odd technically speaking. Hopefully will be clarified later.

 

Edited March 17, 2022 by supercurio

[itsmark]

Chooch hyping up the S20 (as expected):

 

[meepmeepmayer]

The Chooch video above has produced a bit of S20-unrelated discussion about Youtuber drama and whatnot. These post have been split off to here:

[Paul A]

[techyiam]

EEVEES has a new video out. Bradley did a range test and got 73 km's, discharging from 95%-33% battery.  After the West Coast tour, one of the two demo S20's sliders was jammed up.      Starts at 21:45.

 

 

 

[supercurio]

1 hour ago, techyiam said:

EEVEES has a new video out. Bradley did a range test and got 73 km's, discharging from 95%-33% battery.  After the West Coast tour, one of the two demo S20's sliders was jammed up.      Starts at 21:45.

Thanks for the link.

So eevee's experience is a good indication that protecting the suspension rail from ingress in the section between the top and bottom sliding blocks will address the main problem with the S20 suspension.
Now we know that it's not a theoretical issue speculated by Adam - Wrong Way, very real as their S20 was getting stuck with the suspension compressed.

I'm reasonably confident this can be solved with a 3D printed seal in TPU, and already have a basic design in mind (nothing crazy)

Regarding their range test, they got fooled by the erroneous battery % calculation of the S20 like everybody else, and these 33% left were more like 10-5%, as confirmed by speed getting throttled to 40km/h already. So if you extrapolate from 100% to empty (which was almost already the case), 80km top in the riding conditions.
As everybody else, even if the speed target was 45-50km/h you can be sure that the actual riding average was significantly lower, like around 30-35km/h.

It's good to hear tho that although the suspension was getting stuck at the bottom on that wheel, they still enjoyed the suspension very much as it remained effective while riding.

Edited March 18, 2022 by supercurio

[techyiam]

1 hour ago, supercurio said:

So eevee's experience is a good indication that protecting the suspension rail from ingress in the section between the top and bottom sliding blocks will address the main problem with the S20 suspension.
Now we know that it's not a theoretical issue speculated by Adam - Wrong Way, very real as their S20 was getting stuck with the suspension compressed.

I'm reasonably confident this can be solved with a 3D printed seal in TPU, and already have a basic design in mind (nothing crazy)

If the S20 sales volume is as high as we are hearing, the demand for those seals can't be too far behind. As is, it is looking more and more likely the sliders will be high maintenance items.

Even before the sliders got stuck, the polymer bearing blocks could have had abrasions on them, and scoring on the slides. Which all could lead to shorter service life, and more stiction. 

If you have a simple but effective fix to all that, it would be a really big boost for the S20.

 

1 hour ago, supercurio said:

Regarding their range test, they got fooled by the erroneous battery % calculation of the S20 like everybody else, and these 33% left were more like 10-5%, as confirmed by speed getting throttled to 40km/h already. So if you extrapolate from 100% to empty (which was almost already the case), 80km top in the riding conditions.
As everybody else, even if the speed target was 45-50km/h you can be sure that the actual riding average was significantly lower, like around 30-35km/h.

For me, even without a speedometer, I can certainly tell whether I am traveling in the 30-35 kph range or in the 45-55 kph range on my T3 or V12. It is really noticeable. For Bradley, he said he was traveling at speeds that he normally ride at. He was not giving us an average speed. This I like, actually. He said that he was really flooring it on any straights. I would be really surprised if he got duped by the built-in speedometer. I don't think he used the speedometer much, if at all. Either way, we has to ask him to be sure.

He stop the range test when he got a tilt-back at 40 kph. So he stopped the test at the right time then. Of course, a lot of details were left out. It is just another data point.

Edited March 18, 2022 by techyiam

[Curt8892]

Spoke with someone that I highly respect in our EUC community, he had the opportunity of riding a S20 for about 10 km and he was bullish on the S20.  I asked him about the low end torque and the dip that occurred when pushed hard off the line, he advised me that it is there but it recovers. So I asked if he reduced his input to get the wheel to recover from the dip, and he advised he did not change his input.  So this makes me feel a lot more confident that the wheel has more power than it allows you to access. I am good with a wheel that does not let me hurt myself off the line in an intersection. 
 

So still in line for an S20

[supercurio]

5 hours ago, techyiam said:

If the S20 sales volume is as high as we are hearing, the demand for those seals can't be too far behind. As is, it is looking more and more likely the sliders will be high maintenance items.

Even before the sliders got stuck, the polymer bearing blocks could have had abrasions on them, and scoring on the slides. Which all could lead to shorter service life, and more stiction. 

If you have a simple but effective fix to all that, it would be a really big boost for the S20.

Yes I'll give it a shot when I get mine (which might or might not take a while). But in the meantime I'm sure a few makers with access to the S20 prototypes are already working on solutions right now, maybe even testing them as we speak.

My prediction is that on a later batch the S20 will come with similar suspension rail seals out of the box. It will seem odd that the Kingsong forgot them in the first units - just like Inmotion who added extra seals over on their V11 hollow motors bearings.

Edited March 18, 2022 by supercurio

[Tawpie]

4 minutes ago, supercurio said:

My prediction is that on a later batch the S20 will come with similar suspension rail seals out of the box

If we're lucky the delays eevee's spoke about gives them a few more moments??? Batch 1 isn't done yet. 

[supercurio]

27 minutes ago, Tawpie said:

If we're lucky the delays eevee's spoke about gives them a few more moments??? Batch 1 isn't done yet. 

Was it eevee's? Saying that their S20 were assembled already but are waiting for battery packs due to cell shortages.
I agree not too late to have engineers come up with a few designs. It might be tough to iterate and test designs during their lockdown tho.

[Rawnei]

Lukas from eevees said in the latest video that he cleaned and lubed one of their demo wheels, I asked in the comments what the process was like and he replied:

Quote

It was actually quite easy! Here's what I did:

- Took out the suspension assembly for better access (very easy, just remove the 2 thru-bolts)
- Blew compressed air down each of the suspension rails on the inside of the frame to clear out as much gunk as I could. If you don't have access to a compressor with a blowing nozzle, you could wash down the rails with a light stream of water, too.
- Wet a shop rag and pushed it deep into each rail, using a screwdriver to wedge it even deeper where my hands couldn't fit
- Repeated the last step with a new clean rag until visibly clean
- Applied a generous amount of high-quality suspension lube built for dirty/grimy situations
- Re-wiped each rail one more time with a shop rag
- One more application of suspension lube to each rail
- Lifted and lowered the wheel a bunch of times to work in all the lube
- Cleaned, lubed and reassembled the suspension assembly

Done!

Probably about 60 minutes in total? I could definitely have it done in 30 minutes now that I know all the steps

I followed up asking if it's possible for him to make a video about it in the future.

My impression is that this is sort of a "quick" maintenance where you don't remove all the dirt but as much as you possibly can without disassembling the whole wheel.

 

[supercurio]

(possibly) The first S20 customer! A very experienced S18 rider.

(uneasy watching someone ride a brand new 1st batch wheel out of the box without any gear tho)

Edited March 18, 2022 by supercurio

[Tawpie]

16 minutes ago, supercurio said:

watching someone ride a brand new 1st batch wheel out of the box

That's almost certainly the pre-production demo wheel AR auctioned off to support humanitarian efforts in Ukraine. I was very tempted to bid but it got kind of crazy expensive. Listing is gone now. One crazy possible benefit is that the pre-production wheels didn't seem to have factory tilt back turned on.

[Tawpie]

2 hours ago, Rawnei said:

- Wet a shop rag and pushed it deep into each rail, using a screwdriver to wedge it even deeper where my hands couldn't fit

US owners can use their rifle barrel cleaning kit! 

[techyiam]

I am glad that EEVEES mentioned the sliders in the S20 getting stuck in their video. This provides feedback to Kingsong, and perhaps a touch of pressure as well. Not everyone is handy with tools and whatnot. According to EEVEES, Begode has basically no warranty claims, while inMotion has the worse record. If Kingsong is not careful, they may end up joining the club with the most troublesome euc's. And dealers, distributors,  as well as customers can't be happy with that. 

Here is another thought. Are stuck sliders going to be covered under warranty? 

Edited March 18, 2022 by techyiam

[supercurio]

1 hour ago, Tawpie said:

That's almost certainly the pre-production demo wheel AR auctioned off to support humanitarian efforts in Ukraine. I was very tempted to bid but it got kind of crazy expensive. Listing is gone now. One crazy possible benefit is that the pre-production wheels didn't seem to have factory tilt back turned on.

Good question, I asked in comments in his latest video.

I appears his chargers only up to below 124V also (only 1A at 123.7V -  in the CV phase then).
He'll most likely need a new one which can charge fully and balance the packs.

35 minutes ago, techyiam said:

I am glad that EEVEES mentioned the sliders in the S20 getting stuck in their video. This provides feedback to Kingsong, and perhaps a touch of pressure as well. Not everyone is handy with tools and whatnot.

Here is another thought. Are stuck sliders going to be covered under warranty? 

I thought so too and had the same suggestion earlier in YouTube comments. They're the only ones who can really report it to Kingsong since they experienced the issue.
They're great with videos so I hope they have footage to show the issue in details to Kingsong.

[Tawpie]

36 minutes ago, techyiam said:

Are stuck sliders going to be covered under warranty? 

Somewhere KS indicated that the suspension requires routine (monthly) maintenance—clean and regrease. Generally speaking, failure to adhere to the specified maintenance schedule can impair your warranty claim... it'll be up to your reseller in the end though.

[techyiam]

6 minutes ago, Tawpie said:

Somewhere KS indicated that the suspension requires routine (monthly) maintenance—clean and regrease. Generally speaking, failure to adhere to the specified maintenance schedule can impair your warranty claim... it'll be up to your reseller in the end though.

If Kingsong really meant it, they better provide a service procedure with the production models. However, in the end, if they don't have a fix before production, my gut feeling is that it will be messy on more than one level.

To do it properly, it would be interesting to see whether the service procedure can avoid dealing with the permanent locking compound. Otherwise, good luck to the owners. Note that heat would have rendered the locking compound useless. So prior to reassembly, the old locking compound need to be removed first. That will not be a fun job.

[Tawpie]

27 minutes ago, techyiam said:

To do it properly, it would be interesting to see whether the service procedure can avoid dealing with the permanent locking compound

I certainly hope so! Although I think Kevin indicated that the locking compound will be different in production.

 

27 minutes ago, techyiam said:

they better provide a service procedure with the production models

Wouldn't that be nice, right? Kind of like how Mazda gives me the procedure for the 30k mile service interval so I don't have to go to the stealer to have it done. NOT.

[Forwardnbak]

I have to check my v11 chambers for pressure regularly, as long as it’s kinda of easy to clean (like evee mentioned in comments) I’ll be okayish with it. 
 

 

[lazybones99]

Has anyone seen S20 measurements for the width of the wheel well - any chance of getting a 90mm tire on this thing? 🤞

[Rollin-on-1]

2 hours ago, lazybones99 said:

Has anyone seen S20 measurements for the width of the wheel well - any chance of getting a 90mm tire on this thing? 🤞

IIRC Jack said it would take up to a 4" wide tire.  Can't confirm though.  What tire are you looking at in 90mm?

[lazybones99]

18 minutes ago, Rollin-on-1 said:

IIRC Jack said it would take up to a 4" wide tire.  Can't confirm though.  What tire are you looking at in 90mm?

Looking for a summer street tire so at the moment my shortlist is - Michelin City Grip 2, Pirelli Angel or Diablo & Avon AM63

[Rawnei]

Saw on Telegram, ecodrift now has an S20.

So hopefully dissection incoming!