Sensored motors cogging and jittering - WHAT'S WRONG?

@Namasaki good idea, i have a temperature gun.

@flywithgriff and @Jinra, on the trampa motors there are already JST 2mm pitch female connectors.

The motor has this assignment (written in manual): ground (black) phase C (orange) phase B (white) phase A (green) temp (blue) +5 Volt (red)

Beside the fact that the orange cables are brown on my motors (no problem at all) it’s exactly the same pin assignment as on the hall sensor ports on V4.12, the wiring is right (and my extensions).

Well , that’s what I do for now but it’s not really funny to do that on mountainboard with bindings :wink: I’ve tried all modes, the sensors are working, it’s much smoother at low speed compared to sensorless mode but same cogging.

Typically, by convention, white is temp. i wonder if this is a mistake in your manual, or if the manufacturer designed it this way.

It’s designed that way (only the orange cable is brown in my case, or I have bad eyes :joy:) here the original motor JST female:

And blue is 100% the temp because on my Smescs 4.12 (shitty maytech esc) i’ve tried FW 3.26 and could see the motor temp realtime date in Vesc-Tool, so just the cable colors differ, not the pin assignment.

If everything else is correct then i guess it must be your motors. Hall sensors aren’t exactly the most precise thing and can cog as well. I run 120 degree halls on mine, and i occasionally get slight cogging, but it works very well most of the time.

That’s why i’ve tried sensored 6364 190kv maytech motor, too (of course with motor detection, apply and write config) Weird that this maytech motor has exactly the same cogging and sounds equal while cogging as the trampa motors, only when spinning the sound changes. Furthermore I could try sensored 6355 APS motors but I doubt it’s a motor problem.

How about try turning off traction control

Yes actually it’s disabled but no difference. Also tried all 6 possible phase wire combinations as you wrote in a different thread.

What remote are you using ? Have you tried with another model ? Or a ferrit ring on the ppm cable.

I have a steez remote but also tried a old GT2 remote but same cogging. What do you mean with ferrit ring on the ppm cable?

Ferrite rings resolve signal issues… which doesn’t look like what you’re experiencing. I’m at a loss on this. Have you tried removing load (take off belt) to see if it cogs?

The motors don’t cog with belts. So without standing on the board there is no cogging at all and the startup is supersmooth. But when i’m on the board (74kg) there is always cogging.

Im a newbie. But i had some sort of jittering problem with my winning remote. Also shouldn’t max erpm be 60.000 to protection the Drv ?

He won’t go anywhere near 60k erpm, so it doesn’t really matter.

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I just watched your video and do not see your vesc. Are they mounted in the battery box? How long are your battery wires from battery to vesc and how long are phase wires from vesc to motors? This could be your problem.


My wires are like 20 inches and they work fine.


Hi @rich, how long are your cables? The 136kv is good with 60A if you use temp sensors. On a twin you will hardly push 60A.


I’m not sure if the length of the battery cables are measured starting from the battery itself or from the connectors of the battery cables. But if measured from battery wire connectors I’m below 20 cm / 8 inch (as you see on the pic I have an anti-spark switch between battery and V4.12’s (but also tested it without this switch)

Well, I’m one of the world champions regarding phase and hall sensor wire lengths. The phase wires are 12 AWG and about 80 cm / 32 inch The hall sensor extensions are 22 AWG and about 85 cm / 33.5 inch But I’ve tried it with 20 cm / 8 inch phase wires and 10 cm / 4 inch hall sensor extension, too. Hmmm but only with the maytech 4.12’s. Their performance is not like it should be (very poor quality) so I try the short cables with the new @esk8 controller now, who knows?

@flywithgriff yes, as you can see they share the same enclosure. The battery is inside a lipo safe bag and seperated with 0.5mm aluminium sheet from the V4.12’s and the top cover has 2 holes above the controllers. In case of rain i close the holes with fabric tape but anyway, this enclosure is splashproof only, not waterproof.

Hi I am having the exact same problem as you. Just got my E-MTB with 136kw Trampa motors. i have 4.12 maytech vescs, still working…

I have just received delivery of the Vesc 6 so will be installing them next week, would be good to see if it solves the problem. I have been watching Jems Kappel’s video on you tube using vescs and he is wheel spinning on grass, mine won’t even start on grass.

Seems to be no torque in the motor at low speeds and i want torque, not top speed.

Uuuuuuh, do you use the FW 2.18 which is uploaded from maytech? My maytech ones had both the max current ramp step bug (everytime you read or write configuration it gets multiplied by 10). When I read configuration first time, the setting was 40.0 instead of 0.004. Check this before you fry your V4.12! And let me know how VESC SIX performs with this motors, i think i’ll need them, too in the future.

But I have a lot of power at low speeds but not at startup.

[quote=“marcuscrackus, post:38, topic:29245”] I have been watching Jems Kappel’s video on you tube using vescs and he is wheel spinning on grass, mine won’t even start on grass. [/quote] Yeah I know that video but it’s not comparable to his “normal wheelies” I think he prefers raw power of car esc’s on mtb and as far as I know @Nowind even mostly use sensorless motors on his builds. Well I don’t even know if he likes smooth startups :joy: (Isch don’t think so) cogging seems no problem with car esc and full throttle.

Hi, there is plenty of torque. I think your sensor cables are the issue. To long and maybe you use connectors in between. Try to use short cables and no extension connectors. The longer your cable, the thicker it should be. Long cables have a much higher resistance. If your cables get to long you need to amplify/smoothen the signal, using a small PCB, designed for the job. Shielding the cable is also wise.