Endless Sphere

If the "freewheel" is a sprag clutch type, it should be possible to reverse it just by pressing it out, turning it over and pressing it back in.

Hi Stancecoke, thanks for the link to that article.. it contains more information than I had. However, I disagree when you say "it is not contactless": the coils of wire are not physically transmitting current by direct metallic contact: they are electrically insulated from each other, and transmitt...

Re: The TSDZ2 torque sensor: I'm not sure exactly what the communications protocols etc are, or the details of how they do it, but: The coils of wire are large diameter (maybe 3 inch / 80mm diameter?? - I don't have one here to measure) each attached to the rim of a disc perpendicular to the pedal a...

Hi Jean, The torque sensor I replaced was broken in a different way: there was a crack in the tube that carries the pedal torque from the pedal spindle to the main drive gear. I guess there are a lot of these motors in service, but the number of failures we hear about is a bit of a worry.. They are ...

Hi Jeanl, That's a pain to lose two torque sensors! There is a way to get into a buried menu on the controller and see what the output of the torque sensor is. Try this viewtopic.php?f=28&t=79788&hilit=hidden ... 5#p1405380 Getting the timing right in pressing the buttons to get to the buried menus ...

In most builds using Cyclone / GNG etc motors, the motor does not drive the bottom bracket itself.. it drives a chainring that rotates around the bottom bracket but does not apply torque to the bottom bracket. So yes, in a "normal" setup the only torque the bottom bracket will see is the torque appl...

One Chinese supplier of those Sempu Torque sensors has told me that I can have one made to T3 specification, which is the same as the T4 but with ISIS crank connection instead of square taper, at no increase in cost. For serious mountain bikes, that is good news.
Watching your progress with interest!

The Tongsheng torque sensor (photo a few posts back) actually measures torsional strain ( "twist" ) in a tube surrounding the pedal spindle. The pedal spindle is solid and has an external spline near the left-hand end. This spline feeds the torque into the tube, and the tube drives the main gear thr...

Ok, if the magnets line up with that sensor, (and it looks like they do) then PAS sensor seems likely.
It would be great to see a full strip-down of the unit.. it would answer a few questions.

Hi Kisazul, You seem to have access to information / photos of a partially stripped Lingbei motor. I agree it obviously does not have a torque sensor built onto the pedal spindle directly, but in the photo looking into the bore of the bearings there is a dark coloured component with a flat portion a...

Hi John & Cecil, It is obvious that different people ride different bikes in different terrain, and the requirements of each will be different. Just because I want instant response to an increase in pedal torque, and somebody else thinks a gentler / slower ramp up of response is better doesn't make ...

Hi all, I have been interested in getting a Sempu or Bafang (or other make) double-sided torque sensing bottom bracket in ISIS crank format. Sempu (and I think Bafang) have photos and drawings of these on their website but I hadn't found anyone selling them. Finally found a seller on AliExpress that...

Yes, 26" wheels and / or smaller section tires would lower the crossbar a bit. If the tires were the same width, the difference would be maybe 3/4" (around 20mm). Quite an expensive operation for a small difference. Maybe find a second-hand pair of 26" wheels and put thin tires on.. use the 26 wheel...

Hi Emaayan, Re: Torque Sensing BBs: Check the relevant ES thread for more info: https://endless-sphere.com/forums/viewtopic.php?f=28&t=94553 Sempu make various lengths: http://www.sempu.net/newsshow.php?id=1 And although they are hard to find, there are definitely photos and drawings of Sempu double...

It sounds as though the bottom bracket is a separate item (which is good..) On the "Sempu and Bafang Torque Sensing Bottom Brackets" thread, and looking at the Sempu and Bafang websites, there are occasional pictures of ISIS (not square taper) torque sensing bottom brackets. I have looked on Aliexpr...

If they have done a proper job of the design & engineering, it looks interesting. Light weight, thin laminations, compact, doesn't hang down too far, stronger cranks (not square taper anymore!!), decent thick mounting plates.. Wonder if it has torque sensing? If it doesn't have any weak points, and...

Hi MaartenL
Looks like the sprag clutch is slipping. The blue gear is between the motor and the chainring, the sprag clutch is between the pedals and the chainring.
With a blown blue gear, you could still pedal effectively.

"Thanks for the comments. I have some more information which may identify the problem. When the wheel is held stationary the crank arms still turn but with a bit of effort by hand. They even do this when the motor is removed from the housing. Therefore I'm wondering whether the problem may be in the...

Hi All, I have just discovered that one of the New Zealand designed "Smartmotion" electric mountainbikes has a bottom bracket giving both torque and cadence signals, and the control system can be switched easily between torque sensing and cadence sensing at the display. If the Lingbei controller / d...

Hi Arkz, Even though you have given quite a bit of information and a photo, without a circuit diagram or manual it is hard to analyse from a distance. Hopefully somebody who has access to documentation on this motor will read your post and respond. (I guess you have already searched on the internet ...

Hi Phate & HD96, do you guys have access to a multimeter? If you put power to the hall sensors and all your wiring is correct and the hall sensors are working, you should be able to see the hall sensor output voltage rising and falling as you turn the motor slowly by hand. This is a good way to test...

Hi Wayne, For the 36V motor, try Aliexpress: Okfeet sell them: https://www.aliexpress.com/item/Okfeet-eBIKE-tongsheng-inside-motor-for-TSDZ2-electric-bicycle-central-mid-motor-for-replacement-of-36V/32865525984.html?spm=2114.search0104.3.100.7c452cdesMeWMR&ws_ab_test=searchweb0_0,searchweb201602_2_1...

Hi Areus, watching this thread with much interest. I hope you can sort out the problem of freewheeling chainwheels on a strong crankset, because many systems are still based on square-taper cranksets which I believe are too weak for serious offroad riding. I like where you are going, but have you ch...

Looks awesome Matt! Great to see a home-built carbon frame.. something I have thought about myself (too many existing projects to finish first..). Will be interested in seeing how it turns out.

Hi Max H.. Another ES user told me that the lack of a sprag clutch was only one of two differences between the standard and the coaster brake version of the TSDZ2 motor: he thinks it has a different controller as well. With no sprag clutch, it is really important that the motor stops immediately you...