Dual motor single throttle

Can a Bafang BBS02 mid drive motor and a Q128 front motor be controlled with a single throttle? I have put together several two wheel drive combined throttle bikes in the past but have always used matched motors. Has anyone done this?

As you say identical motors and controllers are easy to get to work on one throttle.

What I did for my bike which came with a brushed motor, and the jump bike bafang motor I installed on the front wheel was to put a second throttle on the left side handlebar, I find that I use the original motor most of the time it has pas or throttle and I use the bafang front motor as a boost for hills, or if I have a gear/pas setting that suits the trail I might use the front motor just to catch up with my boss if she gets ahead. I run both motors on one battery, to keep charging simple.

Hwy89 said:

Can a Bafang BBS02 mid drive motor and a Q128 front motor be controlled with a single throttle? I have put together several two wheel drive combined throttle bikes in the past but have always used matched motors. Has anyone done this?

Click to expand...

Here's an example built on a cargo bike platform:
https://talesontwowheels.com/category/dual-motor-awd/

The question is, does the throttle circuit on the Bafang mid drive behave the same as an ordinary hall throttle? +5v —-ground with a control voltage somewhere in between depending on throttle position. If so, it should be able to control both motors. I know it works well on two hub motors.

Hwy89 said:

The question is, does the throttle circuit on the Bafang mid drive behave the same as an ordinary hall throttle? +5v —-ground with a control voltage somewhere in between depending on throttle position. If so, it should be able to control both motors. I know it works well on two hub motors.

Click to expand...

Looks like 5V:

I seem to remember they need to share the ground, but...I've never tried this.

As long as both are run from the same battery, you just power the throttle from one of the systems, and ground it to the same one, then run the signal to both controllers' throttle signal inputs.

If they don't both respond the same way to the same throttle input (like one gives more power/speed/etc than you want at a particular level) you can put a potentiometer into that one's signal line input, with one end of the pot to ground, the other to the throttle's signal output, and the center of the pot to that controller's throttle input. Then adjust the pot until you get just the amount of throttle that controller needs to match the way the other one works.


I have almost always had mismatched controlelrs (and motors) on my 2WD builds of CrazyBike2 and SB Cruiser (only once for a very short time did I have matched ones on SBC), so differing response is something I just got used to...but the pot can help fix that, if you need to.

I cannot get the new Bafang BBS02 and the Q128 front motor to operate using a shared throttle. In fact I can’t get the BBS02 to operate with any throttle other than the one that came with it.
What I have discovered is that if I ride using the PAS on the mid motor, I can add a little power occasionally as needed by using the throttle on the front motor. This actually works very well and I going to leave it as is.
Thanks to all who have offered suggestions.

I am running a 9c 2705 in front, and a Mac powered midrive in back, and I use separate throttles, so I can use either motor, or both, depending on the load, terrain etc. Aw's potentiometer idea, makes me feel really dense! Such a simple solution, it escaped me completely. Doh!
One on each throttle input would allow you even more adjustability.
Ah jeez, now I have to try it, sigh