Kalkhoff Impulse 2.0 battery problem

[zinzet]

can anybody help?
how can I connect non-genuine battery to Kalkhoff Impulse 2.0?

2 thick wires red + black is simple + and -
but there are two additional thin wires white + brown on the bike.

I connect 40v + and - to thick red and black, the display starts, but it shows battery 0% and the engine do not work when I ride.

 

[mlt34]

Can you post pictures? The white and brown wires, what were they connected to on the original bike?

There's a chance that they form a type of ignition wire, where they have to be connected to work. Before you start plugging anything together though, give us a more detailed explanation and perhaps some pictures so we can try to help more.