King Song S18 Discussion

[Ksmack]

8 minutes ago, ssup2406 said:

KsmackBTW how does your upgrade affect the weight, I'm gonna print it for sure, less maintenance=better, can I use something like nylon with even lesser infill to make it lighter?

I think you could definitely print it lighter than what I did. I was a bit paranoid about making sure the panels were beefy enough to handle jump pads for jumps and tumbles at the bike park. I haven’t t done any extensive testing, but I imagine nylon would work with less infill. It would just take some testing. 
 

Even with ASA I imagine you could get away with adding a perimeter wall and reducing the infill. With my settings I think the two panels used about 1.5kgs of material. It definitely ways more than the original shell I think, but that was a bit flimsy. 
 

I could have made the panels thinner, but that makes it harder to use the heat inset screw holders. 
 

I’d recommend printing some smaller test parts to see how those work with less infill. I’d love to know how it turns out!

[The Brahan Seer]

33 minutes ago, ssup2406 said:

Do you all have any other lightweighting tips? I'm planning on taking it on a train with a 23kg limit,

Although the standard S18 is 25Kg's the Molicel version is lighter at 22Kg*. You could ask one of the suppliers who has the wheel to confirm if this is the actual weight.

*According to Eevee's and PET's website.

 

 

[ssup2406]

3 hours ago, The Brahan Seer said:

Although the standard S18 is 25Kg's the Molicel version is lighter at 22Kg*. You could ask one of the suppliers who has the wheel to confirm if this is the actual weight.

*According to Eevee's and PET's website.

 

 

The eevee's website is wrong, I had emailed eevee's because of the discrepancy on many websites, they measured it for me at 53.25 lbs, I do not know why they did not update their website. Their measurement matches with the weight and photo on ecodrift's blog: https://ecodrift.ru/2022/10/12/kingsong-s18-v2-910wh-razbiraem/

Them being businesses I trust that their scales are accurate.

[Tawpie]

One strange thing about the S18 is that it goes together like a puzzle... each piece sets the alignment for the next piece and as a unit they all hold together quite well. I'll have to look and poke around and jog the memory, but the antique brain thinks that structurally you could probably do without one set of packs (both of the short ones if those are the ones you're wanting to drop). Removing batteries will throw off the balance, they're (relatively) heavy.

But it'll be a pretty weak wheel power/safety/speed at 2p. You'll need to be cautious and learn what its limits are, hopefully without hurting yourself.

[daniel1234]

17 minutes ago, Tawpie said:

But it'll be a pretty weak wheel power/safety/speed at 2p. You'll need to be cautious and learn what its limits are, hopefully without hurting yourself.

original cells yes - 20s2p p42a should be capable of delivering 40a continuously up to 65V - if battery is welded correctly. 
For short <10 km commutes 2p it is enough energy. 

[ssup2406]

15 hours ago, daniel1234 said:

original cells yes - 20s2p p42a should be capable of delivering 40a continuously up to 65V - if battery is welded correctly. 
For short <10 km commutes 2p it is enough energy. 

Yes, molicel FTW, besides the power delivery on the motherboard is rated at just 60A right, so not like it'll draw more current than the cells are specced for.

16 hours ago, Tawpie said:

But it'll be a pretty weak wheel power/safety/speed at 2p. You'll need to be cautious and learn what its limits are, hopefully without hurting yourself.

Yes, I plan to do this after like 4 months of riding, from September, that too like a few times a month for just those trips. There's really no transit at the destination, and this is a better option than the logistics nightmare with cars etc.

Can I ask how much do the stock pedals weigh roughly? The Nylonove ones are 850g for the set as per https://www.euc-custom-power-pads.com/nylonove-pedals they are supposed to be one of the lighter ones on the market right? If I could get by with just removing the pedals at the train station that would be waay less hassle TBH..

Edited March 15, 2023 by ssup2406
added "on the motherboard"

[Tawpie]

1 minute ago, ssup2406 said:

Can I ask how much do the stock pedals weigh roughly?

That I do not know—when I bought my wheel (used) it came with Fish inserts in it, and with the Fish inserts the pedals are not very heavy. The pedal's bottom 'cover' is plastic—I think it's basically a cast connection to the hanger with a cast rim. Its strength comes from the Al plate. It'll be dicy... but maybe in transit you could just remove the pedals completely! (one tiny-easy-to-lose grub screw per side, a bit of banging and they're off)

[ssup2406]

Just now, Tawpie said:

but maybe in transit you could just remove the pedals completely! (one tiny-easy-to-lose grub screw per side, a bit of banging and they're off)

Yes that is the plan, on the train here, they often weigh your bags before boarding, not always but often, there's a 23kg hard limit (can't even pay more for extra weight) thankfully PEVs are allowed onboard (change made recently, like 1-2 years ago); they even line ya up like it's an airplane, everything like an airplane except the speed.

[mrelwood]

 

On 3/14/2023 at 9:44 PM, Ksmack said:

I haven’t t done any extensive testing, but I imagine nylon would work with less infill. It would just take some testing.

I think so too. But Nylon is a real ditch for printing large parts. It just bends so badly, the parts probably wouldn't fit together at all.

I'm no pro in printing though, so there could be steps to take and settings to adjust to make it behave better, I just haven't found them.

[Ksmack]

4 hours ago, mrelwood said:

I think so too. But Nylon is a real ditch for printing large parts. It just bends so badly, the parts probably wouldn't fit together at all.

I don’t have much experience with Nylon. I do know with ASA/ABS I need a brim printing in an enclosure to stop warping. There was also some shrinkage.  With PETG warping wasn’t an issue and very little shrinkage. 
 

i imagine with ASA or PETG you could get away printing with a 20% infill. I would still bring the bracket that joins everything at 60% though. This piece is doing a lot of work. 

[NewB]

On 3/13/2023 at 12:02 AM, Ksmack said:

I finally got some time to publish my S18 fairing/side panel design. You can find it here. It is an involved print, but has transformed the wheel for me. After 400 miles of winter riding everything is holding up well. 
 

https://www.printables.com/model/422481-kingsong-s18-side-panel-and-fairing-replacement

 

It is funny - I just posted on Reddit about how manufacturers should spend more time refining and less time "innovating" (and creating new problems). The S18 is a case in point. Despite the fact that there are tons of these out in the wild, the ecosystem is sorely lacking to the point of being almost nonexistent. By now, one would think Kingsong would have developed even a half-ass attempt.

People complain about the body panels - offer an alternative. People complain about the lack of pads - make some that actually work with the wheel. People complain about the battery - offer a piggyback battery mod, rather than run the risk that someone would run out and buy someone else's wheel. People want a serviceable kickstand - design something maybe with fold-out wings for stability or even a solid bumper for the front so folks don't have to scrape up their body panels. Accessories typically bring in a higher profit margin, so why not give people what they want? In addition to bringing in more cash for a lot less work, it shows purchasers the manufacturer is in it for the long haul and is willing to accommodate more than just the initial rush of buyers.

Yeah, they came out with the S20, but you see how that went. Then they wanted everyone to by the S22, then they came out with the S22 Eagle. Those wheels address issues folks had with the S18, but they target a different market. 

[Donaldp751]

On 3/14/2023 at 2:31 PM, ssup2406 said:

Thanks for asking this, I was thinking of the same exact thing today, I don't own the wheel yet but thinking of buying it (need suspension) and lightweighting it further to fit under a 23kg weight restriction that I am faced with, all this unless the V14 comes out with modular batteries which lowers the weight down to 23 with them removed, very unlikely though, plus S18 v2 molicel seems to be a more mature product.

Could I just remove the 2x 10s and run the wheel in just 2p mode when I need to travel with it as sub 23kgs (a couple of times a month)? Would make the wheel rather front-heavy though right, or might not even work if the firmware checks if that battery is connected to the motherboard,

@Tawpie @ffontana @enaon I saw your discussion in this thread about the batteries, could you provide some insight on whether I could roll at 2s?

Do you all have any other lightweighting tips? I'm planning on taking it on a train with a 23kg limit, go figure! There's no transit at the destination so need a wheel for about 7kms itself. It is 24.2kgs per eevee's (email) and ecodrift (their techblog), need to shave off 1.2kgs, I could remove the pedals before getting on the train but unsure of how much that will reduce the weight by.

@KsmackBTW how does your upgrade affect the weight, I'm gonna print it for sure, less maintenance=better, can I use something like nylon with even lesser infill to make it lighter?

Cheers, thanks everybody for reading and potentially responding!

It limits the speed to 30-40 km/hr when you're missing one of the packs. Other then that it will operate just fine without the extra redundancy

[Donaldp751]

On 3/13/2023 at 6:33 AM, daniel1234 said:

Hi, I am coming back to my s18 after riding t4 and master. I borrowed it to a friend at the moment so he can learn how to ride. 
After year of trail usage (but just 3k km), s18 v3 seems like a wheel to keep. It is an amazing lightweight device with a functional trolley handle - ideal for shopping and commuting. I am thinking about what to do next with s18 -> seems like a shame to sell.

- how hard is replace the cell inside s18 ? is it worth of trouble to reuse original BMS? Since I build vesc onewheel I already have spot welder. P42a are easy to buy in eu.
- I would love to have smart BMS for added safety - but since packs are separated it would mean to buy 2x 20s and 2 x10s BMS. Would S18 run without small back batteries connected? If yes I could have just 2 smart BMS in parallel .

Is there any good example of DIY battery mods for S18 where I could look for inspiration? 
Thank you

I'm just getting done rebuilding my S18 (originally LG cells) and replacing with the molicel P42A cells. I used dikes and my die grinder to remove the old cells from the PCB, and clean up the pads for spot welding the new cells on. It's a bit of work, but if you can get the process down it takes about 2.5 hrs to rebuild the smaller packs, and about 4 hours to rebuild the larger packs (starting from tear down, cleanup, prep, spot welding, and testing). I have about 5 years experience working with 18650 packs, and this was my first rebuild with 21700's. It wasn't too bad, just take your time and make sure to cover up conductive surfaces with kapton tape, and put thin foam with adhesive along the edges to help absorb vibration induced from the metal case. 

PM me if you have specific questions about the rebuild.

[daniel1234]

On 3/17/2023 at 5:11 PM, Donaldp751 said:

It limits the speed to 30-40 km/hr when you're missing one of the packs. Other then that it will operate just fine without the extra redundancy

That even sounds like a reasonable limitation.  I will start with small packs if they are not necessary. 

Is there any fancy communication between the control board and individual batteries? (to me seems like there is just middle-pack voltage) I would love to ditch the original kingsong BMS and replace it with something with BT interface to be able to monitor individual cells. 

At same time I would rewire whole battery from "2x 20s + 2x 10s" to "2x 10s2p + 2x 10s" since 10 S BMS are more available around. Cherry on the top would be able to charge via USB-C PD each pack separately.

 

[roro]

Could someone please tell me which of these bolts to remove to change tyre? This doesn't match what KingSong posted for changing tyre on YouTube, maybe because this is the newest molicel batch? 

[Donaldp751]

On 3/23/2023 at 4:09 AM, daniel1234 said:

That even sounds like a reasonable limitation.  I will start with small packs if they are not necessary. 

Is there any fancy communication between the control board and individual batteries? (to me seems like there is just middle-pack voltage) I would love to ditch the original kingsong BMS and replace it with something with BT interface to be able to monitor individual cells. 

At same time I would rewire whole battery from "2x 20s + 2x 10s" to "2x 10s2p + 2x 10s" since 10 S BMS are more available around. Cherry on the top would be able to charge via USB-C PD each pack separately.

 

There isn't any fancy communication that I know of. It's just simple error signals from what I've seen. Very limited from a diagnostics standpoint. The controller is completely unaware of what is wrong with the battery, just a basic error/working signal. It could probably be mocked/simulated with a simple circuit with a few transistors and resistors to make the controller think there is a valid BMS connected. To test this I would just try hooking up a powersupply to one of the connectors (3 normal batteries connected) then use another power supply or resistor voltage divider circuit to get the correct "sub pack" voltages on the smaller pins and see if there is any errors in the kingsong app. If there isn't any errors then I would just put a small voltage divider circuit to supply the correct voltages to the controller PCB. If the BMS you use has an "error" output you could even have your subvoltage pins supplied from the error output so it's able to still detect pack failures. 

[Donaldp751]

On 1/25/2023 at 10:46 PM, novazeus said:

so i just figured out after charging, the s18 isn't turned on, but somehow in standby mode draining the battery. 

if after charging, if i don't turn it on and turn it back off, it's still burning electricity.

weird. i noticed it because sitting there completely off, it will connect to the app.

and the battery drained down to 80% from 100%.

so when u charge a s18, and pull the charger off, the wheel is still "on" bluetooth wise at least.

Are you still having the issue with your S18 not turning off and draining the battery? I had a very similar issue. Some of the symptoms was that it would never fully turn off (if I tilted it down, even hours after riding it was self level once tilted back to level) and it would do the auto shutoff beep every like 90 minutes (or whatever timeout time I set in the app) but never actually turn off. And it was discharge 10-20 % per week, and even after charging, and unplugging the charger it wouldn't turn off. I found the issue on mine, a MOSFET on the control board that controls the logic power in circuit was shorted closed, so it could never power itself off.

 

I'm wondering how common of an occurrence this is on S18's. This controller PCB is one of the earlier rev's, and i'm not sure if later revs have the same issue. I bought a replacement from EWheels and it has a resistor reworked onto the PCB near the gate driver for the mosfet, which may be the "fix" for the issue happening on newer controller PCB's. I'm waiting on my replacement MOSFET from digikey to see if this solves the power off issue, but I have a feeling it will as I removed the mosfet, and can manually jump across the mosfet to power cycle it, and the power button does trigger the gate to shut it off, so it seems likely that this was the problem.

Edited March 26, 2023 by Donaldp751

[novazeus]

9 hours ago, Donaldp751 said:

Are you still having the issue with your S18 not turning off and draining the battery? I had a very similar issue. Some of the symptoms was that it would never fully turn off (if I tilted it down, even hours after riding it was self level once tilted back to level) and it would do the auto shutoff beep every like 90 minutes (or whatever timeout time I set in the app) but never actually turn off. And it was discharge 10-20 % per week, and even after charging, and unplugging the charger it wouldn't turn off. I found the issue on mine, a MOSFET on the control board that controls the logic power in circuit was shorted closed, so it could never power itself off.

 

I'm wondering how common of an occurrence this is on S18's. This controller PCB is one of the earlier rev's, and i'm not sure if later revs have the same issue. I bought a replacement from EWheels and it has a resistor reworked onto the PCB near the gate driver for the mosfet, which may be the "fix" for the issue happening on newer controller PCB's. I'm waiting on my replacement MOSFET from digikey to see if this solves the power off issue, but I have a feeling it will as I removed the mosfet, and can manually jump across the mosfet to power cycle it, and the power button does trigger the gate to shut it off, so it seems likely that this was the problem.

the issue i had when i first got it was, if i unplugged the charger from the wheel first before unplugging the charger from the wall, the wheel would appear off, not balancing, but the bluetooth was still on draining a little power, after a couple days it went down to 80% after a full charge. 

if u unplug the wall first, then unplug the wheel it shuts down, or u can just power it on and off. u can also use ur phone to see if the bluetooth is still on.

[OldFartRides]

11 hours ago, roro said:

Could someone please tell me which of these bolts to remove to change tyre? This doesn't match what KingSong posted for changing tyre on YouTube, maybe because this is the newest molicel batch? 

Welcome to the forum !

yeah, that’s a different set up from the v1 s18. I’d be interested in seeing a tear down of the newer version documented.

[roro]

1 hour ago, OldFartRides said:

Welcome to the forum !

yeah, that’s a different set up from the v1 s18. I’d be interested in seeing a tear down of the newer version documented.

Thank you! I dug through this thread a bit and someone posted a Russian video doing a  tear down of this batch.

Bad news for me is it looks like I need to take off bolts. Bad news because I already stripped one. I don't understand why they would tighten it this much - guess no tire change for me.

[OldFartRides]

Stripped - as in the Allen wrench rounded out the socket while trying to loosen ?

Thats a pain. Maybe it is the thread lock, or maybe an English wrench in a metric cap ?

It will have to come out sooner or later. More deets pls.

[The Brahan Seer]

1 hour ago, roro said:

guess no tire change for me.

Check out something like this to help you remove stripped bolts..

https://www.amazon.co.uk/dp/B08B1N11XD/ref=pe_27063361_485629781_TE_item

I have this set and its worked for me. There are other options available too, check out youtube on how to remove stripped bolts for inspiration and other possible solutions.

If you plan using your S18 in the winter/ rain/ snow much and damp is a problem then I would replace all the screws and bolts with stainless steel. Much easier to do it now than wait for the parts to rust (I would only do this if rust is a problem in your neck of the woods. UK weather is very damp often so it needs to be done but I'm not sure about Toronto.

 

[roro]

2 hours ago, OldFartRides said:

Stripped - as in the Allen wrench rounded out the socket while trying to loosen ?

Thats a pain. Maybe it is the thread lock, or maybe an English wrench in a metric cap ?

It will have to come out sooner or later. More deets pls.

I actually had both metric/imperial sets. Got one loose with a big pop (not sure if that's a sign of thread lock?), second one socket got rounded, third one my dumb ass used impact driver but in the tightening mode 🤦‍♂️didn't bother with the rest.

1 hour ago, The Brahan Seer said:

Check out something like this to help you remove stripped bolts..

https://www.amazon.co.uk/dp/B08B1N11XD/ref=pe_27063361_485629781_TE_item

I have this set and its worked for me. There are other options available too, check out youtube on how to remove stripped bolts for inspiration and other possible solutions.

If you plan using your S18 in the winter/ rain/ snow much and damp is a problem then I would replace all the screws and bolts with stainless steel. Much easier to do it now than wait for the parts to rust (I would only do this if rust is a problem in your neck of the woods. UK weather is very damp often so it needs to be done but I'm not sure about Toronto.

 

Maybe I'll give this a shot. Is there any risk of permanent damage doing this? Like widening the hole too much? Where did you pick up replacement bolts, I noticed all the hardware was really crap/soft, especially the little screws for pedals.

[OldFartRides]

Any bolt or screw that’s compromised really should be replaced. If available, I shop locally. If not, the internets is the world at your fingertips. The one you used impact on - did that strip the bolt threads out ? If so, you will be learning about drilling and tapping to the next size up ! Fun, fun !

[roro]

5 hours ago, OldFartRides said:

Any bolt or screw that’s compromised really should be replaced. If available, I shop locally. If not, the internets is the world at your fingertips. The one you used impact on - did that strip the bolt threads out ? If so, you will be learning about drilling and tapping to the next size up ! Fun, fun !

Thankfully no, I didn't strip the thread, but TIL what tapping is, so I guess I always have options if things go wrong with extraction 😅