Urban Plus Tranzx battery reverse engineering


New Member
We all know the problem with proprietary systems, so lets try and reverse engineer them! My Urban plus battery is showing it's age. A few things should be explained first:
  1. On the urban plus, the bike can be started with the battery, OR the Kobi system through the button or the smartphone
    1. This should mean it's asynchronous? either may start the bike, 2 way communication?
  2. The bike sometimes shows a charging error : "abnormal charging"
  3. The bike will not work with any battery (I have tried with an ebay special 48V battery)
  4. The bike sometimes looses assist if you stop pedaling during a ride, then you have to pedal for a very long time for the assist to come back again.
The above being said, I have started by just using a logic analyzer on the two serial communication terminals on the output of the battery. Here's my results so far:
Screen Shot 05-07-20 at 01.09 AM.PNG
asc II.PNG

So far all I think I know is that it uses ASCII/HEX ???

next I have to capture data between the battery and the bike, while the bike is working.

It seems if I can duplicate the signals between the two with my own battery, the bike should work like, forever! The mid drive is a good unit, with a few quicks, mostly due to the battery I think.

Anybody know about hacking/reverse engineering?

H ebike

New Member
I gave up on my urban plus. I get the no battery found on my cobi. Anyone looking for parts ie. Battery motor, ext. Email me at mikellumi@gmail.com. i am in Hawaii. Make offer plus shipping.