Hub Motor stutters and no torque

Hi guys, I ordered this hub motor from china: https://de.aliexpress.com/store/product/Maytech-Free-Shipping-1pcs-truck-for-single-motor-and-1pcs-70mm-hub-motor-for-electric-longboard/1630416_32820824995.html?spm=a2g0x.12010612.8148356.60.331d43056Wvysp

I attached to the vesc and set the parameters, but the motor has almost no torque at startup. I can hold it with 2 fingers in place. When I push the board a little it’s enough to keep board rolling but thats it, topspeed is like 10km/h

I resoldered the bullet connectors and tested the connection between the phases (shorted, as it should be)

My best guess is a faulty motor or something off with my settings. I took of the sensor to elimate a fault source and did the motor detection. Changing the Current to 1A lets the motor spin. But the result seems off to me, esp the BEMF Coupling is very high. The tool actually caps it at 900. image

The Vesc works fine, I tested it with a different motor. I also tried FOC with sensors mode. That stops the sputtering and gives it more torque. But the top speed is less then impressive. image

Can it be that the hub motor has so little torque? Can I fix something about my settings?

Regards Julian

what are your motor min/max and battery min/max values?

your motor maX and min probably arent configured right :thinking:

image

I set it to 30 Amps, bc the motor is only rated for 22

make sure you do bldc motor detection

but also maybe lower the batt amps? that little motor might not know what to do with 60a :laughing:

Yeah, I did the BLDC, see my first screenshot :slight_smile:

Why would the motor get more then 30Amps when I set the current? When testing with the tool the current never exceedes 3A anyway.

It’s different load and unload. When you are riding the board the current will rise. After you did the motor detection did you apply the values? You have to write them in your vesc otherwise you only did the detection. Plus I see you battery values wrong. Which battery do you use? I guess small for that small motor. - 40 will kill your battery, same for the discharge. Although your motor will never take that much. Please see this video and repeat all the steps https://youtu.be/v1glLDO-EjA

Just out of my curiosity why did you choose this motor over the other well tested? It’s also quite expensive to be a single drive. Good luck

Thanks, I check out the video!

That it doesn’t take a lot of current without load makes sense, but when I block the wheel the current should rise. (More Torque, more Current)

The battery is a 40C 4500mAh, which should deliver up to 200A (constant), the charge rate is not specified, but I assumed it to be around 10C.

Yeah, applied the values. But as mentioned its weird that the detection suggests 1893 for the coupling but when I click apply its only 900. There is probably a good reason for that. My outrunner motor works fine with the vesc.

TBH, I didnt do a lot of research, the requirement was that it needed to be delivered to germany and within budget. There probably is a section for tested motors around here I assume? :slight_smile:

you need to increas the duty and leave the other values as is, as far as i know

Ah ok you use LiPo battery, that’s why the values. Way too much power for that motor anyway. No there is no a section for that and I am totally pro to testing out new thing. I said that because I run hub motor for the past 2 years and they need to be bigger to work better. For the same price you could get way more powerfull motor. Actually even a dual set up. Anyway if you did the all step shown in the video then I do not know. maybe that is the power of the motor. I hope not because it won’t bring you far. The first slightly incline and you are stocked.

Thanks for your help anyway! :slight_smile: I’m just testing things out. The outrunner I had before was way to powerful and heavy so I tried something more subtle. Do you have a recommendation for something light thats strong enough to get me to 20km/h?

I’m gonna resolder the connections and open the motor up. I also contacted the vendor about their controller values.

Most of the hub motors out there come as dual set up. You can pair them with a cheap ESC if you want them as kit or used 2 vesc or a dual unit like the one Flipsky is selling ofr 100 Euro 4.20 hardware. If only need another vecs then take the flipsky 4.12 for 50-60 Euro is a best buy. Hub motor I advice. Diyeboard, meepo, ownboard, wowgo all the same, 90mm wheels. They ar e250Watt except the one from diyeboard 500W. They look the same, but these are the specs. They are 75kv. I have the diyeboard one with a 10s3p battery, 38kmh and great torque. Then if you want something more and still stay in the price, I tested and now organising a group buy for these hub motors. Same as torque board was selling, but I could get it for less then half. https://www.electric-skateboard.builders/t/review-and-eu-usa-group-buy-90mm-mad-hub-motors-75kv-or-130kv-dual-170-euro-1st-round-closed/62002/121?u=rey8801 I advice to use them dual but also singel is possible. 75Kv or 130Kv version. These are really strong. The strongest I tried. Other ones are the maytech one, good motor, but expensive, get too hot and the PU is shit.

So to me in that price range the Diyeboard hubs, or better the MAD hubs.

Yes, I have the maytech one. I heard they are solid, thats why I’m so dissapointed with the performance. I just tested it out again with FOC. It works okay but the torque is really small and topspeed is like 15km/h on a 6s.

Thanks for your advice!

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I was talking about the 90mm maytech one not the one you have

In case you don’t know it:

http://calc.esk8.it/#{“batt-type-lipo”:1,“batt-cells”:6,“motor-kv”:60,“system-efficiency”:85,“motor-pulley-teeth”:1,“wheel-pulley-teeth”:1,“wheel-size”:70}|

You won’t Get any more speed out of it.

Yeah, thanks, did my own math but maybe it went wrong somewhere :slight_smile: I assumed 25V for 6s (fully charged)

Wait, are you testing using the arrows on the keyboard or the remote? If is the keyboard the default max current is 3A, you can change it in one of the bottom tabs on VESC tool

Ah, thanks, thats a good hint :slight_smile: Seems FOC seems to work okay, the top speed just isnt great, even on a full battery.

That’s due to the motor, as I said to small and single. On the other hand is for sure lighter. Next time go for a bigger hub motor if you want torque and speed :grin:

Yeah I expected lower speed and torque, but not that little :slight_smile: gonna play with the configs some more. If I can get it to work in BLDC, i get some extra speed out of it. Also considering to bump up the voltage. It’s officially rated for 8s, has anybody ever experimented with going up to 12s?