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Complete lack of torque on DIY e-bike

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Frazatto
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Complete lack of torque on DIY e-bike

Hello  o/

I got to the point of just guessing and changing values randomly (which is bad of course), so at this point it's better to share tha pain and see if someone have any new ideas.

I'm trying (for more than a year now) to build an e-bike following the project from Tom Stanton (https://www.youtube.com/watch?v=9rIIJbDkpN8&list=PLj3Bh6Krv9CWdRwVFwF1xS_-IQH9GBHyo), the first one that he released on ThingVerse, but now that I have everything in place, nothing actually works well enough and I still can't use it.

Unfortunately all my hardware is chip Chinese stuff, I understand the inherent problems but it's the only ones I can afford.
It's a 6355 190Kv sensored brushless motor, with a 4.12 VESC and 12S3P batteries.

The general problem is a complete lack of torque, it's so disappointing it can't even push me forward in the flat with the bike already in movement.
Already changed to FOC as many suggested in the forum, made no real difference.
If I try to configure more than 35A the only thing I get is a high pith screeching noise, the motor shakes in place and cuts off for a fill seconds (vesc reboots?)
I can really feel some power when I set 50A (the vesc limit), but it only works when testing, the problem just get worse if I try to actually use it for real.

My current theories are:
- Need better batteries? (probably not, they are not even getting warm)
- VESC is shit and can't handle the current? (maybe....)
- The motor is too small for a bike. (this is the one I think is the most likely, considering Chinese specs are all bs)
- The relation is too small and the motor can't handle the load. (this is probably also true considering Stanton abandoned this version, but never released the files for the bigger pulley)

So, if anyone dares to help me, what specific information do you need from me so we can proceed???

s0313045
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50A is the continuous current rating for vesc 4.12 50A, the instanteous current rating is 250A for few seconds.

30A is too weak too do anything, unless your gear ratio provdie a lot of torque.  I would say a motor current of 50A is also not enough.
People building eskateboard/ ebike with vesc usually have their motor current set to around 60A to 80A

 

You can set the motor current to 80A, given that you don't continuously stress the motor above 80A.

Normally, only sudden acceleration or deceleration would cause a high current spike, which usually last less than 2 seconds.

s0313045
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Also, for the vesc turn off situation, give that your motor current is set to 30A, it is very possible that the VESC just throw out a "over current fault/error", and stops for 500ms.

Restore the abs current limit setting to default value, and raise the motor current setting value to 60-80A (I recommend 80A), and try again!

TheFallen
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Don't expect to get more than 30A continuous from a v4.12/v4.20 hardware VESC.

Frazatto
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Ok, I had some time to test it today, made no difference...... perhaps the screeching noise got louder and more annoying!

This editor is supper difficult to use!!! I don seam to be able to quote you directly or attach files.

How may I send you my config files? Maybe you can find something I'm currently not seeing.

Frazatto
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TheFallen, so you think the major problem is the VESC? Unless I upgrade to a VESC6 there is nothing more I can do???

It seams to me the motor is failing big time, why the shaking and scary noise when on load??