Bafang Ultra Discussion

Joined
Aug 13, 2017
Messages
50
Folks,

Opening up a dedicated thread for Bafang Ultra - since we don't have any yet.

Thought this would be good for folks to share / discuss any builds using the Bafang Ultra

Let me start:

Planning to get the Bafang Ultra, set up w/ Grin Phaserunner & Cycle Analyst.

1. Anyone knows if there are any foreseen issues w/ this setup?
2. Will Bafang Ultra's built-in torque sensor work w/ Cycle Analyst?
3. How much amp can the motor handle? I plan to run this w/ 60V (nominal) pack & 50A max amp

Thx!!!
 
couple of things - where do we find frames capable of taking the Ultra motor?

and is the Ultra motor both cadence and torque or just torque only?
 
Just torque, not cadence
As for the frame - I think this is relatively new, so it may take time before we see more getting released to the market. As for the frame, there are a few that offers today, but require a minimum order quantity of 50 :-(
 
agedashidofu said:
Opening up a dedicated thread for Bafang Ultra - since we don't have any yet.

Theres a few about it
https://endless-sphere.com/forums/search.php?keywords=+Bafang+Ultra&terms=all&author=&sc=1&sf=titleonly&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search
 
tommie said:
couple of things - where do we find frames capable of taking the Ultra motor?

I ordered a titanium Fatbike frame for the Ultra in China.
It's almost ready to ship. Will keep you posted.

frameG510.jpg
 
agedashidofu said:
Planning to get the Bafang Ultra, set up w/ Grin Phaserunner & Cycle Analyst.
1. Anyone knows if there are any foreseen issues w/ this setup?
2. Will Bafang Ultra's built-in torque sensor work w/ Cycle Analyst?
3. How much amp can the motor handle? I plan to run this w/ 60V (nominal) pack & 50A max amp


Would love to know that as well.

I have a brand new Ultra here that blew the controller after connecting the battery.
Don't know what to do with it.
Controllers don't seem available.

A Phaserunner could fit inside the casing. There is quite some room.
But only interesting when the Torque sensing function works.

Currently Luna isn't offering the 50A Ludicrous version anymore because of reliability issues.
Don't know if these issues are electrical or mechanical.

bf13.jpg
 
Hillhater said:
Daxxie said:
I ordered a titanium Fatbike frame for the Ultra in China.
frameG510.jpg
Who designed that frame ?
Im not a fan of using the "open" motor support as a key structural frame component in that design.

Well, we will see.
I'm hoping all being titanium it won't fall apart. :)

How else could it be done?
 
Anyone knows if bafang ultra and bafang max have the same mount? Found a nice carbon frame but it says for bafang max, so not sure if the mounts arr the same

Thanks
 
max & ultra mounts are not the same at all.

see Luna's Ultra motor product page, they show the differences.
 
Built mine. See here - https://endless-sphere.com/forums/viewtopic.php?f=3&t=94015&p=1376310#p1376310
 
Does someone knows the purpose & pinouts of the ultra's connectors ? [strike]Also, their make/model would be useful

[/strike] edit: found them, they are JST's JWPF series and are surprisingly IPX7 rated (i.e. no ingress for at least 30min under 1 meter of water) !

here is what I know so far, all viewed from motor-side.

  • 8-pin white female: main EB-bus -> throttle, ebrakes, display uart & power (programming cable attach here)
  • 2-pin blue male & female: lights connectors, 6 Vdc out, 3W max / 500mA (for both or per cable, unknown)
  • 3-pin white female: speed sensor
  • 3-pin white male: gear sensor ? to be confirmed
  • 4-pin black female: ?

What I suppose the black one does is connection to compatible BMS over UART or CAN. The motor would forward the BMS data to the display in order to populate the detailed battery info page (on dpc18 at least) :?:
 
What’s the highest volt battery you can use with the ultra ? I heard that you could go up to 60v with the stock controller.
Not sure if that’s tru.
 
14S (52 volt) battery is highest you can use with stock controller. This charges to 58 volts and 60 is the cutoff point with the Bafang controller.

I pulled their controller and I use the Grin Phaserunner. I can run a 72 volt 60 amp battery.....Currently running 60 volt, 50 amp for 3000 watts. Lot of added torque.
 
Very cool thread. Sold my tangent kit last year when my son was born. 15 lbs later and and the ultra will be my next build. I think 1500 kw will be great as a starting point for me.
 
I just found the manual for the Bafang Ultra but wasn't able to determine what the bottom bracket equivalent of the motor is (please excuse my layman's phrasing), could anyone chime in regarding this?
I am asking because I am contemplating a custom fat bike build where the Q-factor is lower than with the Luna Cycles spindle and cranks.

Hillhater said:
Who designed that frame ?
Im not a fan of using the "open" motor support as a key structural frame component in that design.
Would you mind to elaborate? I as mentioned above, I am in the market for a similar build and would like to know on how this design could be improved.

Ivanovitch_k said:
max & ultra mounts are not the same at all.
see Luna's Ultra motor product page, they show the differences.
Where can I find this information? I searched on Luna's HP but wasn't able to determine it myself.

If you buy the Luna Cycle version you get the magnesium version that is lighter and has the steel instead of nylon cogs, right?
That magnesium version is ONLY available from LUNA, isn't it?
 
El_Topo said:
I just found the manual for the Bafang Ultra but wasn't able to determine what the bottom bracket equivalent of the motor is (please excuse my layman's phrasing), could anyone chime in regarding this?
I am asking because I am contemplating a custom fat bike build where the Q-factor is lower than with the Luna Cycles spindle and cranks.

How can I help?

There is around 17cm distance between the ends of the crankshaft.

61799875_305990820354511_7521033672883961856_n.jpg

The end of the Bafang cranks (pedal side) are around 23cm apart.

22cm.jpg
61993587_2348883912061919_639728193258913792_n.jpg
 
Daxxie said:
El_Topo said:
I just found the manual for the Bafang Ultra but wasn't able to determine what the bottom bracket equivalent of the motor is (please excuse my layman's phrasing), could anyone chime in regarding this?
I am asking because I am contemplating a custom fat bike build where the Q-factor is lower than with the Luna Cycles spindle and cranks.

How can I help?

There is around 17cm distance between the ends of the crankshaft.

61799875_305990820354511_7521033672883961856_n.jpg

The end of the Bafang cranks (pedal side) are around 23cm apart.

22cm.jpg
61993587_2348883912061919_639728193258913792_n.jpg

Merci Beaucoup for posting these images, Daxxie.
So the Q-factor is (give or take) 230mm, this is way too wide for my sensitive knees but what I expected based on the photos from Luna's site.

What I was looking for seems to be the "spindle length" of the motor, according to this document (which seems to be the official ISIS specification).
If I am not mistaken, spindle length determines the chain line (though you can move it around with a spider and/or spacers) and the spindle length + the cranks (meaning how wide they are and how much sweep they have) determine the q-factor.
Taking your measured 17cm from crankshaft to crankshaft, I would assume this about the same as having a 73mm bottom bracket (with the corresponding spindle), but I haven't been able to verify this with my limited knowledge and therefore lack of knowing what to google for exactly.

Again, please excuse my lacking terminology.

PS: Those green tires look rad on your bike!
 
If I get a controller that allows for more watts, would that increase torque besides max speed? I am not after a fast bike but one that can climb steep slopes.

In general, how does the torque sensor of the Bafang feel? I read somewhere that is too sensitive and delivers full power with very little effort, meaning it would be hard to make it feel like the a bicycle and not like a motorbike...
The motor wouldn't bring me any joy if that would be the case, my reference is the "Brose Drive S" motor, does it feel remotely like this? I've ridden the Bosch and found the power kicking in too abrupt and harsh where Brose really felt smooth because it just amplifyed my power input.
Can this behaviour be influenced with the programming of the motor?
 
Daxxie said:
Also found these:
Thank you very much, if I read this correctly this means the motor has a 150mm spindle. That motor bulge might prevent running very narrow cranks if you look at this photo. So a Q-factor of 183mm and a tire clearance of 4.6" as described here might be be out of the picture, though with right cranks one might still be able to achieve a 195(-ish)mm Q-factor with the added bonus of being able to widen the chain stays and therefore run slightly wider tires.
 
Back
Top