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Jan 28, 2021
QS announced the sale of new engines
Снимок экрана 2021-12-12 в 17.46.18.png
Снимок экрана 2021-12-12 в 17.46.34.png

declared characteristics:

  • Power rated 3.5 kW
  • Rated voltage 48-96 Vdc
  • Rated speed 2000 ~ 3500 Rpm
  • Peak torque >= 40
  • Level of protection IP67
  • Type of cooling Air cooling

add after tests:

  • Rating 63 kV
  • No-load current at 4000 rpm about 3.0 A
Nice new motor from QS. :thumb:
That will fit better in a lot of EV conversions being larger in diameter but shorter in length!
I found this on aliexpress:

I imagine that $9,999 is not going to be the final price.
I recently posted about this in a Sur Ron Facebook group.

Basically, the motor will be pretty cheap, like 300$ excl tax/shipping.

The only but biggest issue is that it will only come as encoder version (no longer hall based sensors), meaning that you´d need an inverter that support encoder position tracking. To my knowledge, the most common 3rd party inverters for Sur Ron like ASI or NUC do not support that feature, so you´d have to buy smth like a fardriver controller with encoder support..or get really complex and install a sevcon.
larsb said:
Presale link here:
235usd, not bad :bigthumb:

Wierd, it still reads $9,999 USD for me

EDIT: Oh i get it. Lower down on the page it states:
Notes: It is pre-order link, not the real price.
The sample order is $235/pc.
We will check the production after holiday end, 8th Feb. 2022.
larsb said:
there are also encoders with hall signal output, like renishaw RMC-22 if one wants to add it instead of a microcontroller
I've used this encoder previously, works like a dream :thumb:

so you think we'd be able to physically swap out the one they have embedded in the motor, or mount an encoder like the RMC-22 to the shaft?
It can always be done but impossible to tell best route to go without knowing the internals of the motor.

Preferable would be to remove the encoder that's there and use that space for the new encoder. A 3D printer and some hours of CAD work would solve it (either on drive side or back side).

Buuut, using hall sensors or hall sensor encoder is inferior to having a real encoder so the way i would go is to get the correct controller :wink:
I checked the VESC documentation and they do in fact support encoders. Another problem though is there are a LOT of very smart people on the odrive forum (discord) and there are hundreds of posts reporting problems with noise on the lines of AB-encoders. It's a significant problem. I spent about a year working with odrive and dumped it because of noise issues, it will definitely make me rethink getting this motor.

Three options might be:
1) The RMC-22 is looking very attractive as long as there is an exposed side of the motor axle.
2) Encoders basically work to use two signals to provide a direction and pulse rate that corresponds to speed. I think still think it would be easy to translate that to a form of hall sensor input.
3) Putting a line driver between the encoder and the controller.
4) PWM comes out of the motor as well, which I believe can connect to VESCs. Too lazy to check.

Of those, option 1 would probably be the best.
illegalbike said:
I ordered 3 motors for testing. With delivery to Russia almost 900... The first batch of engines is expected in early April


Where did you buy them? I got a contact person at QS they told me they are still testing the motors and won’t preorder or ship any motors until all the test fases are finished..
It's possible to guess the number of teeth from the diagram of the top of the gear and I get about 24. It's also labeled as 62mm, which would correspond to the correct diameter of a HTD-8M 24t gear.

at a 6.8 gear ratio (which I get to get 50kph from 5-6,000 rpm) that will require a 160t back gear. A short google search did not find any obvious sources for a good gear.
It depends how much power you're running, but you should definitely look up the power rating of a 8m belt at that width, I doubt it's capable of carrying the torque that these motors are capable of.