Help! Erratic controller behaviour - is it a programming issue?

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
I want to find out if the hub motor is acceptable for basic mtb use before considering whether to go for crank drive. I know crank drive is superior, but I only ride mtb occasionally and my skills are basic. Hub drive may be good enough for riding trails and the easier bits of single track at Bedgebury Pinetum. What I don't want is too much or too little assistance at an awkward moment, which seems more likely with a speed controller.

Loading current control firmware to my existing JYT controller would be a very good option, especially as I am only experimenting and would like to avoid complicating the current neat installation with its integrated battery base/controller.

Unfortunately the supplier cannot help. I have tried to identify JYT's website but the only hit is Shenzhen JYT Technology, which seems related exclusively to LCD screens. Can anyone point me in the right direction?
Thanks!
 
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Woosh

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Jytjd.com I did put a link on post #15
 

Woosh

Trade Member
May 19, 2012
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Southend on Sea
wooshbikes.co.uk
BTW, to upload firmware you will need:

1) a USB dongle. Mine has STM32 chip in it.
2) a 4-pin programming connector on the controller.
3) the program to write the JYT file.

It's not all straightforward if you are not OEM.
 

esuark

Pedelecer
Jul 23, 2019
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kent
Bedgebury Pinetum
Ridden an acoustic mountain bike there numerous times winter and summer , if you go regularly get a season ticket to park, or if you go early or late its about half price. Its all on their website. But then you may already know this.

As for a hub drive I`v no doubt if you know how your drive reacts you can accommodate it, I know I could with mine. This is where having brake sensors help. Getting itchy feet just thinking about it now.
 

Nealh

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Aug 7, 2014
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Change the control system over to a KT Kuenteng controller and KT display , it uses current control for power and has five useful power levels 4 giving 13% - 50% of current available and one that gives 100% of current available.
It will work on an mtb as it does on any bike.
 
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Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
BTW, to upload firmware you will need:

1) a USB dongle. Mine has STM32 chip in it.
2) a 4-pin programming connector on the controller.
3) the program to write the JYT file.

It's not all straightforward if you are not OEM.
Sorry Woosh, I missed the hyperlink. Unfortunately it's all in Chinese... can't see a way of changing it to English, or translating in Firefox.

TBH I think you are quite right about it not being straightforward! It's outside my skill set and I don't have the will or time to learn about that side of things. In my case it probably makes more sense to get a KT controller and display.

Thanks anyway!
 

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
Ridden an acoustic mountain bike there numerous times winter and summer , if you go regularly get a season ticket to park, or if you go early or late its about half price. Its all on their website. But then you may already know this.

As for a hub drive I`v no doubt if you know how your drive reacts you can accommodate it, I know I could with mine. This is where having brake sensors help. Getting itchy feet just thinking about it now.
Interesting to hear a practical comment. Encouraging too. So, brake sensors can be useful even without a throttle...

I tend to park up a couple of miles out and ride in - the parking is expensive unles you can fill a car with people, although there is no other entry charge. I didn't know it is cheaper early and late so I'll check that out - thanks for mentioning it.
 

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
Change the control system over to a KT Kuenteng controller and KT display , it uses current control for power and has five useful power levels 4 giving 13% - 50% of current available and one that gives 100% of current available.
It will work on an mtb as it does on any bike.
Sound advice as ever from Nealh :)
 
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esuark

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Jul 23, 2019
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kent
I tend to park up a couple of miles out and ride in
Yes, I did this at first and it was possible back then to park almost right outside but this was stopped. Also another place nearby, too secluded to leave the car in this day and age so got the season ticket. I`d be there first thing Sunday morning breaking all the cobwebs as I rode through the bracken. Two laps then back home. Brilliant on a sunny misty Sunday morning.

KT controller, brake sensors and throttle what more could you want. Well maybe a decent geared hub and 48v.
 
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Nealh

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After my experience with a BBS01 several years ago and two controller failures , I went for a hub motor and KT system for my offroad bike for use on the Downs (N &S) plus the usual trails/tracks /forest routes in between etc,etc in all weathers. If one has seen Eddie PJ's mud rides in the emtb thread then my rides matched some of his for filth and bog mud, the hub never giving me an issue at all.
 
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esuark

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Jul 23, 2019
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Yes, I did this at first and it was possible back then to park almost right outside but this was stopped. Also another place nearby, too secluded to leave the car in this day and age so got the season ticket. I`d be there first thing Sunday morning breaking all the cobwebs as I rode through the bracken. Two laps then back home. Brilliant on a sunny misty Sunday morning.

KT controller, brake sensors and throttle what more could you want. Well maybe a decent geared hub and 48v.
With reference to Bedgebury another place to ride, Bewl Water is nearby where you can ride for free if you find the places on the route around the reservoir you don't have to pay. Rosemary lane on the dam is one of them and its marked on google earth. There are others more secluded and again too secluded for my liking. I "think"its only open April to October.

https://www.google.co.uk/maps/place/Bedgebury+National+Pinetum+and+Forest/@51.062381,0.4201126,2277m/data=!3m1!1e3!4m6!3m5!1s0x47df3e96494cee03:0xad9ce0eb319ab0d2!8m2!3d51.072543!4d0.4477306!16zL20vMDFueTYx?entry=ttu
 

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
More useful comments, thanks.

It was more the weight distribution that was worrying me, but from what you both say it's probably not a big deal, especially as I'm not an expert mtb rider and not looking for technically challenging rides. I'm of an age where if I crash I'm more likely to break than bounce... Any way, hub motor = more traction.

I haven't ridden round Bewl for over 10 years, forgotten all about it lol. It was a club ride from Stonegate Station, SW of Ticehurst. Got a horrible feeling I did it on my old Carrera road bike (no mtb then) ... slow and bumpy, but fun.

There are some good trails down here in East Sussex, as nealh says, but unfortunately I have had 2 1/2 years of long covid since moving from Kent in 2019 and have only started to get fit again this summer. Riding an e-bike for the last year was hugely beneficial to recovery. It's surprising how much exercise you get without overdoing it (bad news while still recovering from LC) on hills and into headwinds. Plenty of both down here.

Off-road riding has been far too strenuous to even think about, but now I'm getting stronger again it makes a lot of sense to motorise the mtb and get back to it.

Sounds like the emtb thread is worth a look.

Thanks again :)
 

Nealh

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Hubs are ok if you don't do jumps , if spoke brake via normal or rough terrain riding then the wheel is n't built very well and needs rebuilding . If rebuilding bets to use a spoke clac to determine the correct spoke length and use Spaim strongs in 14g/2mm size.
 

Nealh

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Sounds like the emtb thread is worth a look.

Thanks again :)
Eddie started the thread when he was a Bosh mud plugger and I somewhere have a few entries but it is a very long thread though withquite alot of pics in it.
 

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
I've cut to the chase. KT 17A SW controller and LCD3 arrived today. I'll bypass the integrated JYT speed controller and just use it as a battery base. I would remove the controller circuit board altogether but the battery connector is fixed to it, so I'll just disconnect it and run power cables through and out the other end. I think 4mm2 stranded cable and a suitable plug should do the trick, unless someone else knows better? Perhaps 2.5mm2 would be adequate? It's only a short length but I don't want it getting hot under load.

Am I right to assume that the BMS would be integrated in the battery itself?

I don't want to fit a throttle, but as I'm now planning an mtb conversion I wonder whether it might be wise to fit brake sensors anyway? The mtb has hydraulic disc brakes, so I'd need to get specific sensors or glue some magnets on. I'd prefer to avoid the additional complication but if safety is an issue that comes first. Not that I'm going to be doing anything very technical (although I'm too old to bounce :() so I could just suck it and see. Thoughts, anyone?

I've been reading an long emtb thread/blog, the 2015 onwards Haibike one, and it's whetted my appetite!
 
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saneagle

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Oct 10, 2010
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I've cut to the chase. KT 17A SW controller and LCD3 arrived today. I'll bypass the integrated JYT speed controller and just use it as a battery base. I would remove the controller circuit board altogether but the battery connector is fixed to it, so I'll just disconnect it and run power cables through and out the other end. I think 4mm2 stranded cable and a suitable plug should do the trick, unless someone else knows better? Perhaps 2.5mm2 would be adequate? It's only a short length but I don't want it getting hot under load.

Am I right to assume that the BMS would be integrated in the battery itself?

I don't want to fit a throttle, but as I'm now planning an mtb conversion I wonder whether it might be wise to fit brake sensors anyway? The mtb has hydraulic disc brakes, so I'd need to get specific sensors or glue some magnets on. I'd prefer to avoid the additional complication but if safety is an issue that comes first. Not that I'm going to be doing anything very technical (although I'm too old to bounce :() so I could just suck it and see. Thoughts, anyone?

I've been reading an long emtb thread/blog, the 2015 onwards Haibike one, and it's whetted my appetite!
I started a thread on brake sensors. See what comments come there. Most of the time, they're not really needed with a KT controller because it has a fast response time.

The BMS is inside the main battery case, so you don't need to worry about that.

14g silicone wire is good for the battery power wires. You don't need connectors because the battery is removable. You can solder the wires directly. In the unlikely event that you ever need to change anything, you can always unsolder them.
 

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
Thanks for the brake sensor comment. That gives me confidence to try without first and see what happens.

Yes, I was thinking in terms of un-soldering the existing short wires from the socket to the PCB and soldering on some longer leads that would connect the socket directly to the new KT controller. The controller has an XT60 male plug, which can be used or removed, as convenient.

Model: KT36/48SVPRD-ffF11L

Wikipedia says 14AWG stranded = 2 sq. mm

I've got some high temperature flex (i.e. stranded), the sort you would use to connect an immersion heater, storage heater, etc. It's 2.5 sq. mm and rated at 25A, so that should be fine?

Now I need to download the setting parameters so I can configure the thing. No doubt the defaults are sensible, but it would be nice to understand what can be changed.

The Someday e-bike accessories store page on Ali Express should tell me what all the leads are for.
 
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saneagle

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Oct 10, 2010
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Thanks for the brake sensor comment. That gives me confidence to try without first and see what happens.

Yes, I was thinking in terms of un-soldering the existing short wires from the socket to the PCB and soldering on some longer leads that would connect the socket directly to the new KT controller. The controller has an XT60 male plug, which can be used or removed, as convenient.

Model: KT36/48SVPRD-ffF11L

Wikipedia says 14AWG stranded = 2 sq. mm

I've got some high temperature flex (i.e. stranded), the sort you would use to connect an immersion heater, storage heater, etc. It's 2.5 sq. mm and rated at 25A, so that should be fine?

Now I need to download the setting parameters so I can configure the thing. No doubt the defaults are sensible, but it would be nice to understand what can be changed.

The Someday e-bike accessories store page on Ali Express should tell me what all the leads are for.
2.5 wire will be OK.

Setting parameters is a lottery. Sometimes, everything is set perfectly, other times they're completely daft.

The first one to get right is to make sure it's set to "torque simulation" P3=1, then it's a case of setting up the PAS and throttle to work how you want them, which is a combination of C4 and P4.

The number of magnets in the speed sensor has to be set P2 =1 or 6.

Occasionally you have to do something with the PAS C1=????

The rest are mainly optional or logical.

 

Slightlypedantic

Pedelecer
Aug 25, 2022
75
10
East Sussex
That's really helpful, thanks.

I've downloaded the manual and had a quick look. Quite a lot of it but obviously it's a case of taking one thing at a time. Each item by itself looks fairly straightforward. The manual looks fairly well written, so I'm sure it will be easy when I know how. Frustratingly, it'll be a while before I get to that stage as I have other commitments, but I'm looking forward to having current control.

I just found an XT60 female/12gauge/silicone cable on Ebay and ordered it. I can just solder the lead ends to the battery base socket, which should make life easier. Then I need to sort out a suitable frame bag to hang the controller in. I assume it's best to keep the power and motor leads as short as possible. This means having a bag in front of the seat tube, possibly a longish one so the controller sits lower down if this avoids the need for extension leads.
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
5,172
2,502
Telford
That's really helpful, thanks.

I've downloaded the manual and had a quick look. Quite a lot of it but obviously it's a case of taking one thing at a time. Each item by itself looks fairly straightforward. The manual looks fairly well written, so I'm sure it will be easy when I know how. Frustratingly, it'll be a while before I get to that stage as I have other commitments, but I'm looking forward to having current control.

I just found an XT60 female/12gauge/silicone cable on Ebay and ordered it. I can just solder the lead ends to the battery base socket, which should make life easier. Then I need to sort out a suitable frame bag to hang the controller in. I assume it's best to keep the power and motor leads as short as possible. This means having a bag in front of the seat tube, possibly a longish one so the controller sits lower down if this avoids the need for extension leads.
The length of wite isn't critical at only 17A.