Tuning af Bird Bike eu-model (Bafang RM G020.250.D)

[Skygge]

Hi,

I've just bought my first e-bike, the Brid Bike A-frame. So far I'm happy with the bike, but there is one thing that I'm a bit miffed about.

Seeing the reviews online (The US and UK) versions (an perhaps earlier firmware versions of EU bikes), you are able to go into the settings and increase the speed limit from 25km/h to 32km/u. I understand fully, that e-bikes going faster than 25km/h, is a different class of electric transportation i the EU, and thus, IF I were to increase the speed limit, the bike would not be road legal.

But, never the less, I would like to make the attempt, and would like to hear if any of you have any advice, because with my limited knowledge of the area, I seem to have hit a brick wall.

the motor is a Bafang RM G020.250.D.

Options that I have read about:

- eggRider controller - I can't seem to find a version there is compatible with this model of Bafang motor
- Changeing the wheel-size: This option is locked in the integrated controller on the Bird Bike
- Cutting the white signal wire to the motor: I'm not adversed to this approach, but it seems like a last resort - and I worry a bit about the motor burning itself out.
- other 3rd party controller/programming: Might be the best option, but I'm at a total loss as where to start.

hope some of you are willing to share your knowledge and advice.

All the best from Denmark

 

[E-HP]

So far I'm happy with the bike, but there is one thing that I'm a bit miffed about.

If you just bought it, I'd suggest just enjoying it as is for a while, since modifying a factory bike isn't a small task and you spent a good deal of money on the bike already. You may find other things you'd like to improve.
I noticed most of the negative comments on this bike are from folks that bought it with the expectation that they could hack the speed limit, and then couldn't get around how the EU locked down the firmware. Seems unfair to judge the bike by that measure, since it looks like it performs well within it's advertised specs.

 

[amberwolf]

Most likely to do what you want you'd either have to:

-- build some simple electronics (Arduino Nano with simple code, or a digital divider/counter circuit) to reinterpret the speed signal (if it is from a separate speed sensor than the motor halls) to the controller so it thinks it is going slower than it actualy is (which will also make the speedometer readout wrong), or disconnecting the speed sensor altogether and replacing it with a signal generator to just give a constant in-limit speed all the time.

--or you'd have to replace the controller and display with something that does do what you want, and is compatible with the battery and motor you have. (the controller needs to not draw more current than the battery is designed for, and has to be the same voltage range as the original. If the motor has no hall sensors you need a sensorless controller).


If the white wire you might cut is a speed sensor, note that many bikes setup with speed limits will either not operate or will timeout and shutdown if they don't detect a speed signal after a short time.

If it's a temperature sensor, then the controller may not operate without the reading being within limits, but even if it does, it won't change your speed limit problem.