New "TSDZ2 Torque Sensor Central Motor"

[sysrq]

How can 10mm offset chainring work if there is only a 1mm gap between chain and plastic cable entry cover when the original 5mm offset chainring is used?
The plastic cable entry cover is quite thick so it can be replaced by a thinner one I guess.
Not sure if 10mm offset chainring could be a solution to stop the friction and wear on the plastic pinion gear cover or not.
Haven't seen any close up pictures with 10mm offset chainring mounted.

because the offset wraps around the motor body. Wouldn't work with smaller chainrings - look at the images on eco-bike site - you can see the offset.

How is that possible for 42t chainring?

look at the pictures on the vendor site - the offset isn't sloping - it's a right angle.

https://cdn.shopify.com/s/files/1/3070/4372/products/20200506_184004_540x.jpg?v=1589397986

I mean close up pictures of the 42t 10mm offset chainring mounted on the motor. I have already seen this one.

 

[gfmoore]

Hi, I've been told by or rather it has been suggested (SloCo) that I should post my questions here. It's rather a long thread to read through all of it and so I'm sure I may find the answers in here already, but at the risk of being flamed, told off and disparaged (as on Stack Overflow!!!) I'll give it a go Be gentle I am ignorant.

So I have built my first e-bike. An alloy framed, carbon forks, 26inch wheel road bike (Forme Longcliffe 4.0), flared drop handlebars (23.8 mm (15/16″)).

I bought a 250Watt, 36 volt Tongshen TSDZ2 mid motor drive. I had also (inadvertently) obtained a 48volt battery and flashed the Tongshen with the stock 48v firmware.

At first I couldn't understand why I wasn't getting up the hills, but then wondered why I had a split cable up from the motor to the 850c controller. The unused end was 3 pin. I had thought it was for a brake sensor (that I had been told by the Chinese seller OKFeet on Aliexpress) wouldn't work with the controller. Then I noticed amongst all the bits and pieces a thumb throttle that I thought had come with a 560c display that I was intending to use. I don't think it did now.

I took a chance, plugged it in and bam, power. I've just had my first road ride since I flashed the motor and attached the throttle and I can't tell you how pleased I am with the power I got and how I can now get up the hills without having a heart attack (I am 61, 5ft 10 and 115kg and very very unfit).

Also that I can still get moderate exercise by pedalling on the flats and up gentler hills. It's great.

However, I now have a number of questions that show my lack of conceptual understanding.

I thought that this motor reacted to torque on the pedals and that using the assist levels would provide, well, more assistance? I have not noted this. There seems to be no difference if I pedal slowly or faster (my normal cadence according to my karoo bike computer is high 50s). I changed the assist level from 0 to 5 and didn't notice anything.

However, when I push on the thumb throttle I get power. It takes a little rotation to kick in and then there is a quickly increasing gradient of power. I even managed to get about 27kph up one long hill - don't tell the cops (It was just great.)

I did try changing the assist levels, but I didn't seem to note any difference, but perhaps my ride was too short to check and changing assist level and changing throttle at the same time is a little unsafe I feel!

So, my questions, after all that are:

Is the throttle taking precedence over the assist levels?

Is the throttle still relying on me pedalling - I did, because I wasn't sure if coasting would be a bad thing, so I was loathe to try it.

Is the throttle necessary? Can the bike be changed to what I thought it would do which is provide assist when I pedal (harder). Though in truth I'm not sure if this is what I would end up doing. I quite liked getting up the hill in this mode, it was why I bought a motor in the first place. (Should I have perhaps gone for the Bafang - oops sorry, I guess swearing isn't allowed here!)

As to the throttle though. It seems to be designed for a right hand operation on a mountain bike type handlebar (22.2 mm (7/8″) ). I can not find one designed for a larger diameter bar?

I think a left hand operation would be best for me. But how the heck am I supposed to mount it? I jimmied a mount, but its not great.

Are there alternatives? I note from my reading that it is a hall sensor. I think that a potentiometer would do a similar thing, but of course without the auto return to zero or perhaps some switches and resistors might do the job, since ot seems to me that I either want the assist or not. Any thoughts.

I'm assuming that it would be a bad thing to have the throttle on and be braking - hence the spring return?

Also I have a hall effect brake sensor, bit was wondering if this could be wired up somehow as it seems to me a good idea to cut the motor when braking.

One great thing about the throttle is when going through lights or starting off from traffic lights. It feels so much safer to be able to get through these without struggling to get to speed.

Thanks for your patience folks.



Gordon

(Moderators, please feel free to move this if not appropriate in this thread.)

 

[raylo32]

If it works with the throttle but not with pressure on the pedals it sounds like your torque sensor may not be working. One way to check is to install the Open Source Firmware which along with the 850C or 860C display allows you to calibrate the torque sensor, during which you will be able to see that it is working from the readings on the screen. You could also maybe open the case up and check it with a meter, but that would be more difficult.

The other possibility... if you mean that you DO get assistance with pedaling but it just doesn't feel like more at the higher levels, it may be that the motor is already working at its max. Based on your weight and such if you test this on a steep hill the motor may already be making its programmed max level in the first assist level. So test it on a flat and see if the bike accelerates easier with less pedaling effort in the higher boost levels.

I thought that this motor reacted to torque on the pedals and that using the assist levels would provide, well, more assistance? I have not noted this. There seems to be no difference if I pedal slowly or faster (my normal cadence according to my karoo bike computer is high 50s). I changed the assist level from 0 to 5 and didn't notice anything.

Gordon

(Moderators, please feel free to move this if not appropriate in this thread.)

 

[gfmoore]

Repeated from original post:

Whilst I'm trying to get my head around this, I'm wondering how the thumb throttle is actually connected.
As I said, the cable from the motor to the display splits near the 850C display, one side has a 3 pin julet connector (now to my throttle), with a six pin julet to the 850C controller.

So is the 3 pin connected to the 850c or to the motor?

 

[gfmoore]

If it works with the throttle but not with pressure on the pedals it sounds like your torque sensor may not be working. One way to check is to install the Open Source Firmware which along with the 850C or 860C display allows you to calibrate the torque sensor, during which you will be able to see that it is working from the readings on the screen. You could also maybe open the case up and check it with a meter, but that would be more difficult.

Thanks for that. Doesn't sound good. It is my intention eventually to flash the OSF, but I am waiting on a julet cable so I can flash the display.

If the torque sensor has gone is it an easy, cheap fix? What would I search for on ebay/aliexpress. I am happy to open up the motor (though I'd rather not just yet) and have multimeter etc.

I'm not sure how it could have blown though. I originally used the 36v battery supplied and the motor as was and wasn't getting anything (without the throttle - I was very unhappy as I didn't get any assist. I expect that, though it's under warranty (well perhaps not since I've flashed it), I won't get much joy out of supplier.

 

[gfmoore]

Man, I hope that isn't the problem, it's not cheap ($100/£70) and a complete disassembly.

 

[Elinx]

Man, I hope that isn't the problem, it's not cheap ($100/£70) and a complete disassembly.

As said. With OSF you can calibrate the torque sensor to work most optimal.
And if your torque sensor is really unsensitive you can do a hardware calibration too.
This is almost the same work as a new one, but without the costs.

 

[raylo32]

I don't fully understand your configuration. As far as I know the motors with stock firmware come only with VLCD5 or 6, not the Bafang 850C. If you are using an 850C then you must have the correct Bafang harness and the connectors are color coded and it should have OSF. If so, go into the menu (hold down up, down and power) then scroll down to technical and check the torque sensor. Since you say you have only 1 small connector I assume you don't have e-brakes so the one small connector will be for the throttle.

Here is the Bafang wiring chart. If you don't have e-brakes you may have a version of the harness cable that omits the brake connectors. I believe they make the harnesses in several versions, T-1( to display only), T-2 (display and throttle), T-3 (display and e-brakes) and T-4 (all of the above).

 

[gfmoore]

Well, when the julet cable arrives...firmware heaven

I have just fully charged the battery and sat on a static trainer. I put it in highest gear 12T at rear and the standard 42T at front. Got up to speed at my "normal cadence" which is high 50s. In assist 0 this was hard for me, but pressing the assist levels it became easier and easier. So I assume that the torque sensors are working at some level. However it is only when I put the device to full throttle that the motor really goes at speed.

Would you expect that the torque provided would match what the throttle provides?

Also I noted in going through the advanced settings,



What do Throttle 6km and Throttle Level do. Do I need to change these?

Sorry, I know the answers will be somewhere in these massive forums.

 

[gfmoore]

I don't fully understand your configuration... check the torque sensor.

Hi, sorry just seen your post.

No this motor came from Aliexpress OKfeet https://www.aliexpress.com/item/33026894805.html?spm=a2g0s.9042311.0.0.27424c4d9yftLA

I had the option of getting the 850c controller which I understood to be the preferred one for modding (Well actually 860c is the preferred one, but it wasn't an option.) I also discovered in my searches a 560c which I fancied as it was seemingly smaller and which I got from Enerprof. I used this at first, but when the motor didn't work as expected I went to the supplied 850c, but it made no difference as far as I could tell.)

The supplier told me there was no brake sensor as the 850c didn't take it. I hadn't realised there was a throttle controller supplied as I didn't think the Tongshen used such a thing.

I backed up the stock firmware and checked with the archived versions and they were the same. As I said I had inadvertently aso purchased a 48volt batter as the supplied 36volt battery didn't arrive and I figured it had got lost or they hadn't sent it. I hadn't realised that I could not simply exchange one for the other without flashing the correct firmware, which I did hoping it would provide more power with the assist. - sorry long story.)

As I said the cable from the motor is y split near the headset area, the 6 pin to the 850c display and the 3 pin to the throttle.

Sorry, what is OSF? Original Stock Firmware??? Edit: No it's the Open Source Firmware, sorry my bad. No I haven't flashed this yet as I cannot flash the 850c display until a cable arrives so I can make the flashing "tool".

What do I check with the torque sensor? Edit: see below and of course since I'm not on the OSF...

Thankyou so much for all your help, I know it must be annoying when a newbie posts what must be very simple and obvious questions and I have spent many hours, days even trying to research this stuff, but my old brain is struggling at the moment to get the concepts. All I know is that something doesn't quite feel right.

 

[gfmoore]

Had a look on 850c controller and cannot see any Torque sensor option.

By the way the battery is showing 54.8 volts, is this to be expected for a 48volt battery?

 

[beemac]

The supplier told me there was no brake sensor as the 850c didn't take it. I hadn't realised there was a throttle controller supplied as I didn't think the Tongshen used such a thing.

Brake sensor signal goes direct to the motor - so it's puzzling that the vendor says it's not supported.. I think it's definitely worth installing them, it should prolong the life of your motor - as unless you're really good at not pedalling at all as you brake you'll strip the nylon gear in the motor much sooner without sensors...

I don't think that's related to your current issue though.

I think you said you flashed the motor controller to a 48v version; from what I've seen - older motor torque sensors have a much less linear response so the value rises much more quickly with lighter pressure - flattening off at higher pedal weights. I wonder whether the stock firmware has been adjusted to suit the newer torque sensor...

I'm musing really - but if you flashed a later motor (with a more linear torque sensor) with earlier firmware - would you then need much greater pedal pressure to get the same assist...since it takes more weight to get teh ADC reading as high...

We'll find out when you install the OSF

 

[raylo32]

That is ridiculous. Tongshen certainly comes with a throttle option. Also ridiculous that about the brakes. But with the 850C and Bafang harness the brakes plug into the motor like the throttle as per the diagram but you need to have the cable that accepts them. This is the opposite as with the OEM displays where the throttle and brakes plug into the display and that then itself plugs into the motor.

And another misconception you have. Throttle power is limited in the TSDZ2. You can only achieve full power pedaling with torque assist, at least in the higher power versions. It may make no difference in the version you have being only 250W, however. I don't know.

Hi, sorry just seen your post.


The supplier told me there was no brake sensor as the 850c didn't take it. I hadn't realised there was a throttle controller supplied as I didn't think the Tongshen used such a thing.

I backed up the stock firmware and checked with the archived versions and they were the same. As I said I had inadvertently aso purchased a 48volt batter as the supplied 36volt battery didn't arrive and I figured it had got lost or they hadn't sent it. I hadn't realised that I could not simply exchange one for the other without flashing the correct firmware, which I did hoping it would provide more power with the assist. - sorry long story.)

As I said the cable from the motor is y split near the headset area, the 6 pin to the 850c display and the 3 pin to the throttle.

Sorry, what is OSF? Original Stock Firmware??? Edit: No it's the Open Source Firmware, sorry my bad. No I haven't flashed this yet as I cannot flash the 850c display until a cable arrives so I can make the flashing "tool".

What do I check with the torque sensor? Edit: see below and of course since I'm not on the OSF...

Thankyou so much for all your help, I know it must be annoying when a newbie posts what must be very simple and obvious questions and I have spent many hours, days even trying to research this stuff, but my old brain is struggling at the moment to get the concepts. All I know is that something doesn't quite feel right.

 

[gfmoore]

I've ordered a bafang harness.

With regard to stock firmware, when I first got the bike I used the 36volt with the motor as is, and experienced the same low effect that I'm getting now.

Am I expecting too much? Sadly I don't know anyone round here (Stoke-on-Trent UK) with an ebike. At least with the throttle I can get up the hills.

How do the throttle and pedal assist interact though. Are they separate effects.

My understanding is that the more you press on the pedals the more power is supplied (at various levels of assist), also you need to keep up a cadence (60s) to get the power. I'm assuming that when I use the throttle it just provides power to the pedals depending on the output voltage from the throttle.

Thanks for the help.

 

[raylo32]

I don't know what to tell you. This isn't the strongest motor but it should get you up the hills whilst pedaling if you put in a proper (low enough) gear for the grade and your weight and don't expect too much. And to say again, the pedaling assist should be greater than the throttle, especially on the higher assist levels.

Here is a link to the TSDZ2 from one of the vendors here in the US listing the standard configuration they sell. It contains a good bit of product information. Note the sentence about the throttle.

https://www.eco-ebike.com/collections/tongsheng-tsdz2/products/tsdz2vlcd5

I've ordered a bafang harness.

With regard to stock firmware, when I first got the bike I used the 36volt with the motor as is, and experienced the same low effect that I'm getting now.

Am I expecting too much? Sadly I don't know anyone round here (Stoke-on-Trent UK with an ebike) At least with the throttle I can get up the hills.

How do the throttle and pedal assist interact though. Are they separate effects.

My understanding is that the more you press on the pedals the more power is supplied (at various levels of assist), also you need to keep up a cadence (60s) to get the power. I'm assuming that when I use the throttle it just provides power to the pedals depending on the output voltage from the throttle.

Thanks for the help.

 

[sysrq]

Hi, I've been told by or rather it has been suggested (SloCo) that I should post my questions here. It's rather a long thread to read through all of it and so I'm sure I may find the answers in here already, but at the risk of being flamed, told off and disparaged (as on Stack Overflow!!!) I'll give it a go Be gentle I am ignorant.

So I have built my first e-bike. An alloy framed, carbon forks, 26inch wheel road bike (Forme Longcliffe 4.0), flared drop handlebars (23.8 mm (15/16″)).

I bought a 250Watt, 36 volt Tongshen TSDZ2 mid motor drive. I had also (inadvertently) obtained a 48volt battery and flashed the Tongshen with the stock 48v firmware.

At first I couldn't understand why I wasn't getting up the hills, but then wondered why I had a split cable up from the motor to the 850c controller. The unused end was 3 pin. I had thought it was for a brake sensor (that I had been told by the Chinese seller OKFeet on Aliexpress) wouldn't work with the controller. Then I noticed amongst all the bits and pieces a thumb throttle that I thought had come with a 560c display that I was intending to use. I don't think it did now.

I took a chance, plugged it in and bam, power. I've just had my first road ride since I flashed the motor and attached the throttle and I can't tell you how pleased I am with the power I got and how I can now get up the hills without having a heart attack (I am 61, 5ft 10 and 115kg and very very unfit).

Also that I can still get moderate exercise by pedalling on the flats and up gentler hills. It's great.

However, I now have a number of questions that show my lack of conceptual understanding.

I thought that this motor reacted to torque on the pedals and that using the assist levels would provide, well, more assistance? I have not noted this. There seems to be no difference if I pedal slowly or faster (my normal cadence according to my karoo bike computer is high 50s). I changed the assist level from 0 to 5 and didn't notice anything.

However, when I push on the thumb throttle I get power. It takes a little rotation to kick in and then there is a quickly increasing gradient of power. I even managed to get about 27kph up one long hill - don't tell the cops (It was just great.)

I did try changing the assist levels, but I didn't seem to note any difference, but perhaps my ride was too short to check and changing assist level and changing throttle at the same time is a little unsafe I feel!

So, my questions, after all that are:

Is the throttle taking precedence over the assist levels?

Is the throttle still relying on me pedalling - I did, because I wasn't sure if coasting would be a bad thing, so I was loathe to try it.

Is the throttle necessary? Can the bike be changed to what I thought it would do which is provide assist when I pedal (harder). Though in truth I'm not sure if this is what I would end up doing. I quite liked getting up the hill in this mode, it was why I bought a motor in the first place. (Should I have perhaps gone for the Bafang - oops sorry, I guess swearing isn't allowed here!)

As to the throttle though. It seems to be designed for a right hand operation on a mountain bike type handlebar (22.2 mm (7/8″) ). I can not find one designed for a larger diameter bar?

I think a left hand operation would be best for me. But how the heck am I supposed to mount it? I jimmied a mount, but its not great.

Are there alternatives? I note from my reading that it is a hall sensor. I think that a potentiometer would do a similar thing, but of course without the auto return to zero or perhaps some switches and resistors might do the job, since ot seems to me that I either want the assist or not. Any thoughts.

I'm assuming that it would be a bad thing to have the throttle on and be braking - hence the spring return?

Also I have a hall effect brake sensor, bit was wondering if this could be wired up somehow as it seems to me a good idea to cut the motor when braking.

One great thing about the throttle is when going through lights or starting off from traffic lights. It feels so much safer to be able to get through these without struggling to get to speed.

Thanks for your patience folks.



Gordon

(Moderators, please feel free to move this if not appropriate in this thread.)

27 km/h seems impossible on a long steep hill with 36V(42V) battery on mine. It barely holds 12km/h on a 6% 100m long hill with a current fluctuating between 10-15 Amps@35Vm voltage sag which is maxed out on 42t×32t gear. So with a throttle only it wouldn't make it at all.

 

[gfmoore]

And to say again, the pedaling assist should be greater than the throttle, especially on the higher assist levels.

...Note the sentence about the throttle.

"Throttle (the optional throttle is governed and will not put out as much power as the assist function - this is to increase longevity and reliability of the motor)"

Yes very weird.

@sysrq
Yes I was (happily) amazed at my speed. It wasn't a very steep hill - I'd have to check it's gradient (edit: 3-6% about 1km) - but the bike was fair motoring up it and as I said I'm 115kg... (This was speed from the Karoo.) I was pedalling, but not with maximum effort, just as though I was on the flat.

 

[gfmoore]

deleted.

 

[gfmoore]

I've just seen this in an article on https://www.electricbike.com/tsdz2-750w-mid-drive-torque-sensing/#comment-10789

One TSDZ2 Quirk

“…There’s one problem that happens virtually every time it’s used by a new rider. The unit calibrates the torque sensing every time its switched on, and 95% of riders put one foot on a pedal and then turn the unit on, don’t ask me why, it’s just that the majority of riders seem to. By consequence, the calibration of the torque assist is way out of kilter and you get almost no assist…”

Do you think this is what could have happened to me? Is it true?

Apart from the OSF (see I'm learning the lingo ) is there an interim solution - re-flashing the stock firmware? Resetting the 850c to factory defaults? Or since I connected the battery before sitting on it am I just mis-reading the quote?

 

[raylo32]

Yes, that will screw things up, even on OSF. Basically it sets the weight you have on the pedal at zero and then you have to press harder than that to see any effect. But the solution is simply the next startup it recalibrates itself. Just don't be on the pedals then.

Here is a good programming guide if you want to reflash OEM (and even OSF) sometime for whatever reason.

https://www.eco-ebike.com/blogs/eco-cycles-instructionals/tsdz2-motor-firmware-programming

I've just seen this in an article on https://www.electricbike.com/tsdz2-750w-mid-drive-torque-sensing/#comment-10789

One TSDZ2 Quirk

“…There’s one problem that happens virtually every time it’s used by a new rider. The unit calibrates the torque sensing every time its switched on, and 95% of riders put one foot on a pedal and then turn the unit on, don’t ask me why, it’s just that the majority of riders seem to. By consequence, the calibration of the torque assist is way out of kilter and you get almost no assist…”

Do you think this is what could have happened to me? Is it true?

Apart from the OSF (see I'm learning the lingo ) is there an interim solution - re-flashing the stock firmware? Resetting the 850c to factory defaults? Or since I connected the battery before sitting on it am I just mis-reading the quote?

 

[sysrq]

And to say again, the pedaling assist should be greater than the throttle, especially on the higher assist levels.

...Note the sentence about the throttle.

"Throttle (the optional throttle is governed and will not put out as much power as the assist function - this is to increase longevity and reliability of the motor)"

Yes very weird.

@sysrq
Yes I was (happily) amazed at my speed. It wasn't a very steep hill - I'd have to check it's gradient (edit: 3-6% about 1km) - but the bike was fair motoring up it and as I said I'm 115kg... (This was speed from the Karoo.) I was pedalling, but not with maximum effort, just as though I was on the flat.

The true hill length more likely was aroud 100-500m. Seems like the TSDZ2 is only useful on really short (10-30m) and steep hills (17%). In these conditions it can achieve anywhere between 12-17 km/h when starting from a stop depending on a day. Probably it doesn't like the pedalling technique (needs to be at the certain programmed cadence and torque level to combine/tease out the leg power and motor power in the most efficient manner, otherwise both are working against each other).

 

[raylo32]

17% is a steep hill. We have some of those (and steeper!) here we ride our pedal bikes over but I haven't tried the TSDZ2 bike on anything much more than about 6-8% which it handles easily. If you do the real steep stuff the key is to shift to a low gear just like you would if pedaling to keep the motor in its happy zone. And a bike with the standard 42t TSDZ2 chainring might not have a low enough gear to be happy. That is one "problem" with this motor, it is so quiet it is hard to tell what it is doing... unlike the CYC X1 Pro Gen 2 on my MTB. That one gives plenty of audible feedback.

The true hill length more likely was aroud 100-500m. Seems like the TSDZ2 is only useful on really short (10-30m) and steep hills (17%). In these conditions it can achieve anywhere between 12-17 km/h when starting from a stop depending on a day. Probably it doesn't like the pedalling technique (needs to be at the certain programmed cadence and torque level to combine/tease out the leg power and motor power in the most efficient manner, otherwise both are working against each other).

 

[gfmoore]

Found this post:
https://www.endless-sphere.com/forums/viewtopic.php?t=99597#p1459575

Re: Tongsheng TSDZ2 not providing assist. Fine on throttle
by Jez » Apr 16 2019 1:35pm

So for those following this thread, turns out that it was not the rotation sensor proximity after all. The bike was working really well right up until the point when the battery got low. Recharged the battery and the problem is back. The battery is a home built 48V and my current theory is that the controller is not happy at a higher voltage. Could it be that if I can get it used and the voltage drops then that will sort it? In some ways it makes more sense than the proximity issue before. Done a fairly extensive search and nothing out there helps much. New controller perhaps...

What is also worth mentioning is that after a full charge nothing much works at all As I play with it on on the stand, progressively there is a much greater chance that the motor will spin up when I advance the throttle. Initially it would do nothing but seems to work more and more as time goes by. This is so weird.

In an earier post I said I had noted that the 850c battery indicator was showing 54.8 volts which seemed to me to be high for a 48volt battery, but what do I know.

Any thoughts?

I suppose I need to drain the battery a bit and see.

 

[raylo32]

No, that sounds about right. Remember the 48v is your nominal battery rating, whilst full charge for a li ion cell is ~4.2v... so 4.2v x 13 cells = 54.6V.

In an earlier post I said I had noted that the 850c battery indicator was showing 54.8 volts which seemed to me to be high for a 48volt battery, but what do I know.

 

[gfmoore]

I'm still trying to find answers from the entire internet on what settings I should have?

Poles in motor = 1 doesn't sound right? More like 6 perhaps. However, I don't want to damage the motor (anymore than it might be?) by just changing numbers at will!!!