cassette Torque-sensor Hubmotors

[mechaniker]

a torquesensor is for me a must have Item to get a normal bike-riding-feeling.

The bottom-braket-sensors make to much trouble in my eyes and the most of them have an old style square-tapered axle as someone who crack those axle´s easy with my 150kg I have spend a lot of time in Hospital for those rubish crank´s.

So I was happy when I found Kclamber-Sensor in China and saw it is already used inside a few motor-brands and my Employer "Lishui-Controller" already have a controller for those motors. So I can use my shimano hollowtech-II crank or my ISIS crank

I bought all motors with those sensors that I could get a hold of and tested them. First to say it is the best solution so far for torquesensor Hub-Motor bikes but as an old school german technician there was always something to complain about, motor to noisy, to heavy, to unreliable, to weak and so on.

The best Motor during testing was the Aikema with this sensor but a 2kg motor is a bit to weak in my opinion so I asked Shengyi-Motor why they don´t implement this sensor into their "x2" Motor because it would be a perfect combo but their boss has zero interest into it so I did convert that shengyi-x2 Motor that I had in my office on my own into a Kclamber cassette Sensor motor

The result of my "X2" Motor conversion is exactly what I´ve expectet, a new benchmark for hubmotor pedelec, powerfull and noiseless. Noiseless is a very important point to me because when I´m riding a bike through nature I don´t want to hear anything from the motor. Some say "if you hear the sprockets it is not so bad" but for me it is nightmare


Advantage of the Kclamber sensor: only 3 connectors you need to connect to get a high level ebike with Torquesensor. Just Battery, display and Motor, there is nothing on the crank anymore. All is inside the hubmotor The Motor is connected by U-art to the controller and transmit all the time data-packages to the conntroller. The response of the sensor is way better and more sensitive as if you have a bottom-braket sensor.
I will search for more motors with this sensor when I fly to china hopefully somewhere in the next few weeks and if I find one that you can just plug and play I keep you posted



It is the future for better ebikes with hubmotor on a same level as well known centermotor from germany or japan

 

[K2@home]

Hello Mechanicer,

I live in holland , have an engineering background and i work in aviation
I am intersted in coverting an old mountainbike to ebike with a maximum speed up to 35 km/h for commuting to the airport. (2x20km a day)

The mtb has an press fit hollowtech 2 cranck . I was wondering the same as you, why not build the torque sensor in the cassette hub!

I have no expierence with ebike motors . what type of motor , battery and controls would you recommend ?? is it all compatible or do i need all the parts from one brand??

the pictures you made Look very promising.
The 6 bolts from the casette , are they just installed in the motor cover ??

 

[mechaniker]

Hi K2@home,

Like I said, no motor that I´ve driven so far has convinced me, only the one I made myself I would give recommendation but you can´t buy it for now...

yes, the 6-bolts of the sensor are just installed into the motorcover

there is no ready solution for your purpuse that you could just buy in a shop somewhere that I know about.

You need a powerfull motor like the one I´ve converted for the speed of 35kph that you want, even in flat netherland. I assume you know that in whole europe which include Netherland is a speed limit of 25kph for standard pedelec! All above 25kph is no longer a pedelec, it is a small motorbike and need nearly the same testing and paperwork..... not easy to get and fore sure not without additional cost (emc testing is alone a few thousand euro)

You need a controller that can work with the sensor-signal of the cassette, thats why a friend of mine developed the special pcb which I needed to solder into my motor because the standard PCB which is inside the motor can´t be used.
We, "Lishui-Controller" (lsdzs.com) have such controller for plug & play but you can´t buy a single controller from us since we don´t deal with consumer who only want "1-pcs" controller...



As display I use on all of my 6 bike´s a Key-display kd-1386. I like it since I don´t like tablet sized display on my steering ;-) and it is easy to use even with gloves in winter because no tiny bottons for changing the step that you are in.... just push the display and the step change to less when push the bottom of display or goes up when push the top of the display


To get a ready set you need to wait a bit, maybe after chinese new-year there is a ready set.

I know a chinese company who´s preparing and testing a lot of different motor with the goal putting together a complete "plug&play" set.

I will fly to my colleagues in china soon for discussing a complete Set in this matter.

 

[Woosh]

how do you install the X2 kit if your motor has in-built speed and/or PAS?

 

[mechaniker]

speed-signal, PAS-signal, torque-signal all signal come now from the casstette and goes through the white cabel of the standard 9-pin Motorconnector by u-art transmit to the controller. So no change in motorcable connector is necessary but of course a different pcb inside the motor and a different controller architcture with an additional u-art port inside the controller for receiving the the data-packages from the cassette-sensor.
Nothing anymore to install on the crank, a troublemaker is simply erased from the map of pedelec conversion-kit

it is like in early times when BIONX came to the marked, you only needed 30min to go from a normal bicycle to a high-end pedelec

 

[Woosh]

I did use a torque sensor built into the motor in 2013-2014. Link. Saneagle tested it and pointed out the weakness of torque sensor in the hub: the amplitude of the response depends on the gear you are in and it hits the limit pretty easily. I now use a bottom bracket TS. Have you got a solution fot that?

 

[mechaniker]

If I see it correctly, you used xofo-motor?

I myself assume to know every single Torquesensor useable for hub-motor ebike on the marked and have tested them all in my private bikes (still are in my office from Thun, Sempu, erider, Ncte and so on). Additionaly, when I visist bikemanufacturer across whole europe as an employee of "Lishui-Controller" I get a lot of feedback from the manufacturer because Torquesensor is my hobby, I even invented a torquesensor for Hollowtech-II crank-set from Shimano on my own and recently sold the prototyp to a chinese bike company.

the explanation of "saneagle" in case of foc-controller is wrong if his explanation has belonged to FOC in combination with internal hubmotor-sensor. But I remember at that time many companys had tried to use cheap controller in combo with torquesensor which didn´t worked out, the first torque-sensors from China and the controlling of it, it was a nightmare and the bb sensors too. At that time I made for myself a cheap problemsolver and carried with me in case my bb-torque-sensor has gone broken during a biketour (the internal PAS sensor inside the bottom-braket torquesensor usually didn´t go broken) With a laptop I could have solved the problem by software but who carries a laptop during a bikeride;-) my problemsolver has looked like the enclosed photo and was maybe 6cm by 2cm which matches with every pocket in your trowsers. You just had to connect my problemsolver between torquesensor connector of the controller and the connector of the sensor itself to solve the problem quickly. In result you could ride further with your bike like a normal PAS bike with power-steps but without torque-sensor comfort and you could bring your bike to the workshop when the timing matched your needs. It was a downsize in comfort but at least you could still ride with electric support

Then came Bionx and showed how to make it right but they did made other things wrong. But from the ride-feeling it is still a benchmark in my opinion. Kclamber is now on the same level but easier to handle in aftersales and cheaper. Reliability? can´t tell since it is a new approach but it seems very promissing to me and actually I´ve trust in it.

Now to your question,
my english ability might not be good enough to explain why the speed/rpm that you are in doesn´t matter that much at all by using FOC controller..... same principle that you have with modern centermotor where it also doesn´t matter which gear or speed you are in only the force that you use on the crank-axle is necessary to know then you only need to write the software accordingly. Same goes for the cassette axle, only the force that is meassred on the axle is important and this doesnt change by the gear you are in. Just some fine tuning is left according to the motor that you use for hugh differences in motor torque-output but the software that I use now is 99% good for most motor in the 250 watt range. For example you need to adjust the settings if one motor is weak and then you connect a powerfull 50nm torque motor to the same controller setting you get shocked about the force the motor support you so you need to adjust down the Percentage inside the steps ;-)
The amplitude you smooth away by software anyways to get a smooth riding-feeling

with FOC controller you can controll the motor output in relation to your own effort meassured by the sensor which also has nothing to do with rpm or cadence, just the torque-signal. You could bring meassurment of cadence and rpm into the loop but it isn´t realy necessary and the software become complicated. We, Lishui brought those meassuremnt into the loop because we need to produce something that is not based on my liking but most customer liking so we can adjust more as it actually necessary to adjust

sadly,
A few years back I visited our "Lishui" customer in britain and dealer sometime by car and could carry testing bike´s with me to let them make a test-spin but since brexit I don´t do this anymore because I don´t have time to waste on a stupid border-controll that the brexit of course naturally has caused. If you would come to a bike-exhibition in the EU we could meet there and I bring a bike with this combo of controller and motor with me for a testride....If you would come to cologne airport which is just 30min from my office I would pick you up, you could make a testride fly back an hour later if you don´t want waste money for hotel and so on

btw, sorry for long blabla...., sometime I have trouble to keep myself short

The photo shows the two parts of my problemsolver for broken Torquesensor BB that I made for myself, first you need a switch on delay by 4sec because without it the bike could jump when you switch it on. Thats the right part of the photo and the left part send instead of the of variable torque-signal a continious voltage to the controller which you could adjust for your prefered needs by a pot. The PAS-signal just go through to the controller like it did before and the bike rides with this combo as a power-step bike

 

[Woosh]

If I see it correctly, you used xofo-motor?

Correct. At the time (2014), the xofo motor was connected to a Lishui controller. I gave up on this kit a long time ago, so can't remember accurately how it was done. If I remember correctly, the torque sensor output was connected to the throttle input.

 

[Woosh]

I think this is a great invention.