Help! Building up from Swytch kit

[cheesemonkey]

Hello fellow ebikers,

I've been posting few questions around Swytch kit (bought Oct 2020, second generation, PRO model) and how to upgrade the build using more widely available components.

Well, the time is nearly here to ditch the Swytch kit. The hub motor judders and whines very loudly. Upon inspection one of the phase wires from the controller is melting away at the connector (green wire, and the connector has fused itself). It's unsafe and I'm not prepared to risk it anymore. Just about 3.5yrs of use and nearly 4,000miles of travel (and far too many issues to overcome...), I'm pretty content to let it go.

I could just get a whole new front (or rear) motor conversion kit from say, Woosh, Geeko, Yose Power, etc for another £500ish. But I want to prevent waste and use up as much components from the current kit (and save few pounds by doing so).

The components from Swytch kit are:

Hub Motor:
36V 250W 100SX-6XX-36H-S (assuming it’s Aikema AKM 100SX hub, not sure what other codes mean). Looks like a typical 9pin Julet connector (image from Swytch website):



Controller: LSW1452-1-6F (36V, max 12A, rated 6A, protection 31V, throttle 1.2-1.4V)

Pedal Assist Sensor PAS: KT D12L (left-side)

Display: can’t find the model detail but very basic led display, but it's this:


Battery: 36V 7Ah (250Wh) - Generic Chinese battery wrapped in blue shrink thing. My previously failed pack went for £55 on eBay (for spare/repair).

Charger: Looks very much like T120P 36V 2A, two pin inlet (from wall) with DC barrel jack outlet (to battery) like below:



With thanks to all the advice so far (mainly from this thread, before it got hijacked by others with Sywtch issues...: Swytch kit: compatibility with non-Swytch components? | Pedelecs - Electric Bike Community), I feel I can keep the hub motor (AKM 100SX), PAS (KT-D12L), charger (assuming it's universal for 36V batteries) and display (maybe? looks universal; I only need a display just to turn on/off and set speed limit to 15.5mph for legality).

So I'm assuming (with limited knowledge) that all I need is a new battery / controller set + extension cable to connect the motor, battery, PAS and display (1-2 cable enough, I assume).

My needs & wants for new build:
- 36V 10Ah is more than plenty for 20mile commute each way (I can charge at work)
- I prefer a downtube battery but rack option is also considered
- Battery pack with integrated controller for simplicity
- I prefer, if option allows, 9MOSFET than 6MOSFET to cope with countryside hills (I think Swytch's Lishui controller is 6, based on my experience of having 3x controller fails/cables melting).
- Simple display: Just to turn on/off, check battery level, set speed limit to 15.5mph, and maybe change assist level. Not concerned about other stats (odo, speedo, volt, etc.)

My questions are:
- Has anyone ditched Swytch kit and upgraded battery/controller/display to work with Swytch motor?
- Will something like this from TopBikeKit be a straightforward build?: 10S2P HT-2 Mini Bottle Battery 36V10AH Samsung 21700-50E Cells+ KT Inner Controller [HT-2 Battery 36V10AH] - $170.05 : Zen Cart!, The Art of E-commerce (topbikekit.com)
- What's the trade off with downtube battery with integrated controller?
- Is there anything else to consider before building on to Swytch's hubmotor or just simply better/safer to get a whole conversion kit from scratch?

Many thanks as always and happy cycling.

 

[cheesemonkey]

Oops, I've just spotted very similar thread further down (@FrTedCrilly from Dublin ):

Any update/experience on alternate battery and controller options to use with Swytch front wheel ? ( eg. Geeko) | Pedelecs - Electric Bike Community

Doesn't seem to have an update from his experience so it would still be valuable to hear people's thoughts on my questions.

Happy cycling.

 

[Nealh]

The akm 100 is good for 36v/20a but if at 48v then consider 15/17 a as max.
Those bottle batteries are ok, though one has to watch the pair of blade contacts in the base as over time the contacts spread a fraction due to the action of the battery removal/insertion . So they need to gently pressed together for contact to be made again with the bottle .
Bottle mount will fit on the seat tube if you have 330mm height having come out 90mm horizontally for it to fit . Less conspicuous then fitting on the down tube.

Any KT and lcd set up will be hunky dory, it just depends on how one want's to mount them.

You can keep the 12DL PAS set up and simply select C1/7 in the settings for it to work.

 

[Cisco-man]

The display is what Swytch call the Base Display. It has a M6 5-pin Julet plug that won’t directly fit any other situation (other than Swytch) - as everyone else uses M8 5-pin Julets, if Julets are used. It might work with another Lishui controller but there’s no way of easily telling. They sell for around £20 on ebay so might be better to just sell it on.

 

[cheesemonkey]

Thanks @Nealh and @Cisco-man.

Also I realised there was an absolute gem of a thread further down by @throwawaychap: Confused and looking for 48v 250w rear hub since Yose won't sell me 250w 36v kit with 15ah battery. Wealth of detailed information and it has been so valuable for me to dig further in.

Considering the Julet plug size incompatibility for Swytch's basic display (thanks @Cisco-man for the heads up), I also wonder if the PAS plug is also not in the standard size (the Julet plug out of the handlebar bracket looks bigger than the Julet plugs inside the PowerPack, so maybe PAS plug size is standard?). I thought the upgrade display for AIR/MAX is KT-LCD4 so I automatically assumed the Julet plug is standard, but yes, the plugs are smaller within the PowerPack.

So, just to be safe; I am leaning towards just simply getting a whole new conversion kit + battery.

Thanks @Nealh for your usual wisdom. The controller amp suggestion is interesting, Swytch's Lishui has max 12A and rated 6A. Perhaps my commute elevation (350-370m per leg) and pre-school runs that I used to do (hauling two toddlers on a trailer) was too much to handle for the controller...
It's been a revelation, and also reassuring that I’m on the right track, to read @throwawaychap's thread. I've been looking at Yose Power, Woosh and TopBikeKit (rejected propriety brands such as Geeko, Kerbebike, Cytronex, etc), but haven't quite found a kit that I feel happy to commit to.

Yose Power uses Lishui controllers, which my experience with Swytch has caused a dent in the confidence on Lishui (fairly or unfairly). TopBikeKit sells KT kits and possibly cheapest option (maybe not anymore with customs tax?); but it’s a direct sale from China and I’m worried I might get burned again if there are any issues. Woosh uses Lishui as well and King-Meter (KM529) display and tracked reputation for great customer service. Why doesn’t Woosh supply KT? I’m curious to know.

Is there a UK seller with good service which sells whole kit with KT controller and display? I haven't found one and I'm guessing it’s down to me to find the right combination to make the kit myself.

I’m quite happy with front hub 36V 250W set-up for simplicity and occasional commute, but I can be persuaded otherwise. My commute is 18.5mile per journey (Whoosh predictor suggests 13-15Ah for return trip, which is spot on in my experience of 7Ah Swytch pack, depleting to one level at end of each journey). I do this commute 2-3x week with my own steam on another bike. Occasionally I need to do extra day in the office or I’m just tired, so that’s when I take the ebike.

I did consider 48V but probably an overkill for odd commutes and occasional recreational pootling with our youngest toddler on frame mounted child seat (no trailer anymore). Considered rear hub, but the rear triangle gets caked in grime even with full mudguard; especially on winter commutes (farm lanes…). I don’t have the time/space to wash down the bike every ride. I'm also concerned about exposure of degreasers (to clean the drive train) and gradual ingress to the internals from the wash over long period of time. Front hub feels easier to simply wipe away the muck and quicker to remove the wheel completely for thorough bike clean.

What a valuable forum this is. Thanks everyone for making the time to share your knowledge, wisdom and experience.

Happy cycling!

 

[Woosh]

Woosh uses Lishui as well and King-Meter (KM529) display and tracked reputation for great customer service. Why doesn’t Woosh supply KT? I’m curious to know.

it is because the difference in approach between KT and Lishui.
KT let the customers set up the parameters for their controllers while Lishui supplies firmware to OEMs. Being an OEM, I can select which firmware to use to minimise support issues.
The result is clear: nobody asks how to change the firmware settings for Lishui here whereas every month, we have members asking how to correct the setting of their KT controllers.
There is also the misconception that KT controllers are better than Lishui's.
Lishui is a lot more popular among OEMs for good reasons: reliability, fast microcontrollers, quality firmware.

 

[Nealh]

Lishui aren't suited to the diy market as they are near impossible to buy or match with an after market LCD or so that is why KT are so popular, with Lishui one is tied again to one seller who has programmed them.
The KT one can't programme any firmware but simply change a few parameters to suit which ever motor is used and which type of differing PAS signal is used.

Folks like d8veh , Harry in the US and I never have issues with our settings as we know which ancillary items we are using.
One reason fourums like this are in existance , we are one of the worlds greatest LBS's and our online repairs are free.

The AKM 100 will support 20a @48v if one uses the power carefully other wise best to stay at 17/18a , at 36v one will be fine with 22a but at that current I would opt for a 9 mosfet controller and any above 15a.

 

[cheesemonkey]

it is because the difference in approach between KT and Lishui.
KT let the customers set up the parameters for their controllers while Lishui supplies firmware to OEMs. Being an OEM, I can select which firmware to use to minimise support issues.
The result is clear: nobody asks how to change the firmware settings for Lishui here whereas every month, we have members asking how to correct the setting of their KT controllers.
There is also the misconception that KT controllers are better than Lishui's.
Lishui is a lot more popular among OEMs for good reasons: reliability, fast microcontrollers, quality firmware.

Many thanks Woosh for your transparency, very much appreciated.

It sounds bit like a comparison of Windows and Macintosh - KT (like Windows) allows end-user to configure / customise the system (trade-off is that the user needs to know what they're doing) whilst Lishui sounds like the configuration is pre-set at point of sale.

Does this mean Lishui controllers are "locked" (i.e. no option to customise / re-configure once firmware is set) or "pre-set" (pre-configured at sale, but alteration is possible, potentially at user's risk)?

I'll do some more learning around KT vs Lishui.

 

[cheesemonkey]

Lishui aren't suited to the diy market as they are near impossible to buy or match with an after market LCD or so that is why KT are so popular, with Lishui one is tied again to one seller who has programmed them.
The KT one can't programme any firmware but simply change a few parameters to suit which ever motor is used and which type of differing PAS signal is used.

Folks like d8veh , Harry in the US and I never have issues with our settings as we know which ancillary items we are using.
One reason fourums like this are in existance , we are one of the worlds greatest LBS's and our online repairs are free.

The AKM 100 will support 20a @48v if one uses the power carefully other wise best to stay at 17/18a , at 36v one will be fine with 22a but at that current I would opt for a 9 mosfet controller and any above 15a.

I can understand this argument @Nealh. I feel it's down to the user's preference (plug & play, or customise until your heart is content).

My thoughts are: if I were to keep Swytch's 100sx hub, then I think KT route is appropriate. If I were to go for the whole new kit and I have no interest in fettling with the kit, then Lishui is fit & forget.

 

[Woosh]

Many thanks Woosh for your transparency, very much appreciated.

It sounds bit like a comparison of Windows and Macintosh - KT (like Windows) allows end-user to configure / customise the system (trade-off is that the user needs to know what they're doing) whilst Lishui sounds like the configuration is pre-set at point of sale.

Does this mean Lishui controllers are "locked" (i.e. no option to customise / re-configure once firmware is set) or "pre-set" (pre-configured at sale, but alteration is possible, potentially at user's risk)?

I'll do some more learning around KT vs Lishui.

If you want to install new firmware, you can use stm32 programming kit.

 

[cheesemonkey]

Mainly for my own note taking... I've done some more digging and there are actually similar threads here of people who bought a Swytch kit and wanting to move on / upgrade /customise the kit using more widely available components. Threads like these have been useful for me:

Converting from Swytch to standard equipment
Settings for KT Controller and Swytch Hub
Swytch kit: compatibility with non-Swytch components? (this was my thread a year ago)

Also TopBikeKit (TBK) is very useful to find more about components and their specs / compatibility.
Also found KT Setting for LCD3 (including description of P and C parameters)

Some things that I've taken note:

• Swytch's Hub: It's 100SX 250W 36V, not 36/48V (according to TopBikeKit's 100sx) so that rules out 48V? It doesn't provide the hub rpm info but assuming 201rpm for 700C size (either 201 or 328 according to TBK website)
• Controller Ampere: Could go max 17A at 36V (612W?) for 250W hub. Swytch's controller was max 12A (432W), rated 6A (216W). I might have pushed it too much with hilly commutes and towing kids on trailer?! Looking at TBK website, I can only find T06S 15A (rated 7A, that's 540/252W) on TBK. 15A sounds capable enough without passing on the risk of damage to the hub?
• Controller MOSFET: I know understand @Nealh's experience on getting a controller with 9MOSFET for better tolerance to higher current and reduce risk of overheating. So I could also get a 9MOSFET controller (e.g. T09S - max 22A, rated 11A) and then set the max current to 15A on C5 parameter (C5 values 04 =14.7A; 05 =16.5A).
• Controller signal: Sine vs square wave; sine is preferred for gradual output (square is sudden burst) so why does square wave controllers still exist (square wave sounds dangerous)?
• Controller plug types: small block (SM) vs Julet connectors; SM is easier to troubleshoot with multi-meter, but will need a bag for protection. Julet is neater but difficult to troubleshoot.
• Controller location: external vs battery integrated controllers; external can tuck in excess cable length but requires a separate bag. Integrated is hidden in battery holder but more difficult to troubleshoot and excess cables need to go somewhere.
• KT Display: My preference is LCD5 for simplicity and then LCD11. LCD4 is simplest but reliability seems hit/miss?
• PAS Poles: 8PAS (or 6 / 10 poles) seems to be more reliable than D12L? Seems like many conversion kits come with 12 poles though?
• Throttle: get one for testing (and I might change my mind about using it when riding).
• 8Pins Extension Cables (Julet): 1-2 is for throttle and display. 1-4 is for throttle, display and brakes.

 

[cheesemonkey]

For anyone curious what's inside Swytch generation 2 PRO/ECO battery pack...

 

[thelarkbox]

IF for example your wishlist is for a 17a sine wave controller to hide inside a hailong battery slide with Julet connections an 9 mosfets and a ktlcd5 and cables to connect to your brake sensors and pas etc so 1 to4 or 1 to5, email that to tobikekit and see if they can provide it, thier controllers are a bit of a list to wade through..

They invite email queries so take em up on it

But a small tidy triangle frame bag can hold a few more things than just a controller like a few tools

fwiw i went with julet connections and regret it.. the seal on itself silicone plumbers tape can cover and seal anything

Pas sensor, the cheap and cheerful left side mount all in 1 12 magnet sensor is easy to fit but if your bike is of the cheaper type its crank may be a tad over the expected 17mm in which case the one part sensor could be troublesome. the 2 part sensors all have the same weakness/flaw, the magnet disk can get knocked out of whack.. those that hide the magnet disk on the right side behind the chain ring are less susceptible to knocks effecting the magnet ring.

with a kt controller configuring it to enable a throttle when pedaling so legally is do-able, so fit one and use it if you want.

I applaud the homework, i was more quick look and dive in head first

 

[cheesemonkey]

So narrowing down to few possible options:

1. Woosh (whole new kit with wheel + battery): MXUS XF07 front hub 250W 36V, Lishui controller (18A sine-wave), King Meter LCD, 13AH HL downtube battery (Samsung 18650-29E cells). Price around £500?
2. Yose Power (whole new kit with wheel + battery): 250W 36V 40Nm front hub (brand?), Lishui integrated controller (15A), LCD (brand?), 15.6Ah HL downtube battery (18650 cells). Price £375 (currently out of stock but can purchase the front kit + 13Ah battery separate for the same price).
3. DIY A (controller, display, PAS + battery): KT controller (T09S 22A or T06S 15A), 9Pins Motor Cable to SM blocks, KT LCD5. Price ~£80.00 for the kit. Plus HL downtube battery (10-13Ah) from somewhere.
4. DIY B (TBK kit with battery): HL2 downtube battery kit (14Ah Panasonic NCR18650GA cells, integrated 15A, LCD5, 8PAS, 130D throttle). Price ~$500.00 (~£390.00).

I haven't got to thinking about the details of how to wire up the kit to the bike. If going with external controller set-up, then perhaps I could have a little handlebar bag to manage the cables.

I also wonder if I can be clever enough to somehow salvage the 7Ah battery from Swytch but it might just be easier to flog the battery pack as spare/repair on eBay.

 

[Woosh]

Woosh (whole new kit with wheel + battery): MXUS XF07 front hub 250W 36V, Lishui controller (18A sine-wave), King Meter LCD, 13AH HL downtube battery (Samsung 18650-29E cells). Price around £500?

the 13AH battery is made with older technology, no match for the new batteries made with 27100 cells.

 

[StuartsProjects]

I will be jumping on my eBrompton to go shopping later.

Its got a Swytch front hub motor from a previous Brompton conversion, but I dumped the controller battery bag and fitted a standard KT controller and battery in a bag. LCD4 display. Standard PAS sensor on the chainwheel side.

 

[cheesemonkey]

the 13AH battery is made with older technology, no match for the new batteries made with 27100 cells.

Thanks very much @Woosh for the detail. I haven't considered this. It looks like the options I listed are all 18650 cells. I can see on your webpage that the battery bag & rear rack options are 21700 cells. What is the minimum Ah do you supply with 21700 cells?

 

[Woosh]

Thanks very much @Woosh for the detail. I haven't considered this. It looks like the options I listed are all 18650 cells. I can see on your webpage that the battery bag & rear rack options are 21700 cells. What is the minimum Ah do you supply with 21700 cells?

That depends on the donor bike.
It's best having a chat with Andy. He is online a few hours a day on the website livechat or call him.

 

[cheesemonkey]

Its got a Swytch front hub motor from a previous Brompton conversion, but I dumped the controller battery bag and fitted a standard KT controller and battery in a bag. LCD4 display. Standard PAS sensor on the chainwheel side.

Thank you @StuartsProjects. If I were to go the DIY route (i.e. keep the Swytch hub motor), then this is exactly my thought. I even pondered if I can recycle the PowerPack bag (empty the Swytch controller and battery) by putting a new battery and controller. It is a small bag so it might be tricky to get new kit in it (plus keeping the incoming/outgoing cables tidy). So I thought it might just be easier to get rid of the Swytch set up (bar the hub) completely.

 

[Nealh]

The switch akm100 doesn't care what voltage it receives so 48v is fine, what will occur is it will run 30% faster so will depend on the initial motor RPM winding.