Bafang Motor H840 RM G0900.750.D/DC

[Arnaud WOODALPS]

Hi all,

I'm converting a bike to electric, with a H640 48V RM G0900.750.D/DC hub motor from Bafang, a grin Baserunner controller hidden in a Hailong battery case, a T17 torque sensor, and a 600C display from APT. I was seaching for info about the H640 motor (750W), notably the number of pole pairs and the gear reduction to set the correct parameters in the Grin controller.
As I did not found anything on the forum and elsewhere, I have opened the motor to be sure.

There is 10 pole pairs (20 magnets) and a gear ratio of 1:5 (15/30/75 teeths)

I just wanted to share the info, I hope it will help.



I'm still struggling to make the correct connection between the Higo mini connector of the APT 600C UART display with the Baserunner harness, I don't have the info about the pinout on the display connector. If someone has details, I'm interested.

This e-bike conversion is for my father. I also buit wooden bikes, but i do not yet have a dedicated ebike model. Just a glimpse of my wooden bikes :

This is the gravel. I will will use the MTB model for the Ebike conversion.
My brand is WOODALPS, this is just a secondary activity.

 

[Mikelon]

Hello,

Could you please tell me the size of the axle on the H640 750w G0900 hub motor ?
Is the axle 14mm x 10mm ? I am thinking of buying this motor for myself.
Or is the axle 12mm x 10mm ? It looks like a 12mm axle to me. Bafang should have upgraded the axle to 14mm for the torque level this motor can provide with the right controller. MAC and BMC motors are using 14mm axle on their geared motors of the same power level for years now.

Thank you in advance!

As a thank you from my side, as you requested information, I have attached my pinout picture I created for the APT 600C display connector. This is a correct pinout for 600C display, specifically with UART protocol.
However, be advised that Baserunner controller from Grin obviously support KM5s protocol.
And your 600C display has UART communication protocol. So, it's not a guarantee that even if you connect everything correctly, that the display and controller will work correctly, because of the different protocol.

 

[Arnaud WOODALPS]

The axle is 14mmx10mm. The nut is quite big (you will need a 22mm wrench). I've purchased a slightly smaller nut as I will use a torque arm.
Thanks for the info about the display. I purchased the 600C display from Grin, and thought it would be compatible, as it is clearly detailed in the description on Grin website (600C Integrated Handlebar Display and Switch) that it operates on KM5s communication protocol. In fact, it is compatible, but only if their Main9 Superharness is used (and this is not clearly described on their website), but they don't sell it alone yet, so I'm a bit stucked on this project. I will try to setup the system headless until I can purchase the SuperHarness.

And their pinout is different from the one you have shown, probably because it is not UART Protocol, even if the display name is also 600C.

 

[Mikelon]

Thank you very much for your reply, regarding the axle size. Finally Bafang has realised that a thicker axle is necessary, I am glad about it.
Years ago, MXUS has manufactured their 3K-Turbo direct drive 3000w (nominal !) motors with only 14mm axles. Many users have broken the 14mm axle, as the motor is so powerful. But then eventually MXUS has realised their huge oversight, and they have upgraded the axle on 3k-Turbo motors to 16mm.

Regarding your 600C display: if you have bought it from Grin website, then of course it has KM5s protocol, and a pinout which has been specified by Grin team themselves.
As you probably understand: I thought that your 600C display had a UART protocol because you mentioned in your post, I quote: "APT 600C UART display". 600C UART displays are usually used for Bafang mid drive (BBS02, BBSHD etc.) and for some Bafang hub motor controllers. And for Bafang controllers, UART protocol, and Bafang 1t4 wiring harness, the pinout I provided would be certainly correct. But not for your 600C display from Grin, because that display is customized. The 600C display from Grin not only has a different pinout, but also a custom firmware in it, which enables the display to by used even with 72v batteries.
600C UART displays with standard firmware for Bafang controller can only be used for 52v batteries for now.
But everything is clear now for both of us.
I hope that eventually you will be able to buy a wiring harness separately from Grin.
Good luck with your project!

 

[Narbthetoeless]

Hi all,

I'm converting a bike to electric, with a H640 48V RM G0900.750.D/DC hub motor from Bafang, a grin Baserunner controller hidden in a Hailong battery case, a T17 torque sensor, and a 600C display from APT. I was seaching for info about the H640 motor (750W), notably the number of pole pairs and the gear reduction to set the correct parameters in the Grin controller.
As I did not found anything on the forum and elsewhere, I have opened the motor to be sure.

There is 20 pole pairs (20 magnets) and a gear ratio of 1:5 (15/30/75 teeths)

I just wanted to share the info, I hope it will help.

View attachment 349635 View attachment 349636 View attachment 349638

I'm still struggling to make the correct connection between the Higo mini connector of the APT 600C UART display with the Baserunner harness, I don't have the info about the pinout on the display connector. If someone has details, I'm interested.

This e-bike conversion is for my father. I also buit wooden bikes, but i do not yet have a dedicated ebike model. Just a glimpse of my wooden bikes :
View attachment 349639
This is the gravel. I will will use the MTB model for the Ebike conversion.
My brand is WOODALPS, this is just a secondary activity.

I bought the same motor and also use a baserunner but with a CA 3. Would you be willing to share a few screen shots of your parameter settings on the phaserunner suite? Are you using the temperature parameter? I seem to have a bit of an issue with overcurrent faults. I can’t seem to find an explanation. Also I think Grin make a new adapter wire for your setup. (You probably know this)

 

[Arnaud WOODALPS]

I bought the same motor and also use a baserunner but with a CA 3. Would you be willing to share a few screen shots of your parameter settings on the phaserunner suite? Are you using the temperature parameter? I seem to have a bit of an issue with overcurrent faults. I can’t seem to find an explanation. Also I think Grin make a new adapter wire for your setup. (You probably know this)

I try to show you the parameters tomorrow.
They effectively have an adapter, the superHarness that I should use with the 600c display I bought from Grin, but they only sell it as part of a kit (controler + motor + display + sensor +...). So I still can't finish my bike. I will maybe order a CA3 to be able to use my bike, and order a superHarness when it will be available for purchase.
From what i understand, the H640 bafang motor doesn't have a temperature sensor.

 

[Arnaud WOODALPS]

I bought the same motor and also use a baserunner but with a CA 3. Would you be willing to share a few screen shots of your parameter settings on the phaserunner suite? Are you using the temperature parameter? I seem to have a bit of an issue with overcurrent faults. I can’t seem to find an explanation. Also I think Grin make a new adapter wire for your setup. (You probably know this)

Hi, the main parameters for my motor / battery configuration are detailed below.

 

[ShardCollector]

Hello and thank you for the info!

Bafang claims that the motor is compatible with 7 - 11 speed cassettes, but doesn't give any measurements or cassette standards.
So, my question: is it Shimano HG? Or some other standard?

A guide to freehub body and cassette compatibility

Can’t figure out what freehub body you need for a certain cassette type? This will help.

velo.outsideonline.com

Edit: My Bullitt has the choice to change dropout to traditional 10x135 mm quick release or 12x142 mm thru axle. Some site claims that Bafang needs 138-142 mm O.L.D. size, but clearly it doesn't fit the 12 mm thru axle dropouts? Do you think it would fit the 135 mm quick release ones?

https://www.larryvsharry.com/da/dropouts

Sorry for so many questions! It would be nice if Bafang told these things straight on their page!

 

[Nixunen]

There is 20 pole pairs (20 magnets) and a gear ratio of 1:5 (15/30/75 teeths)

20 magnets is 10 polepairs not 20.