Modding a cheap ebike controller (similar to ecrazyman's)

[cajunjay]

Hi guys

I did have a standard ebike controller off ecrazyman but it blew before I got a chance to put some 3077 FET's in. The controller was fairly cheap and I had problems from the start with it until a resisitor was soldered across the C20 which then made the bike rideable allbeit with hardly any power.

I wanted to know if any cheap ebike controller can be modded with new FETS and the other few things that need doing Shunt etc to get the same results? Or am I wrong as maybe whoever found out about the mod of soldering a resistor at the C20 had tried alot of things before working that out. Meaning if I was to buy any old controller I would have a hard time finding where the resisitor would need to soldered in.

Hope that makes sense :?

 

[el_walto]

You can find controllers for such good prices that it might not be worth your time. Buying a cheap controller, cutting out functioning parts and replacing them just doesn't seem worth it to me.

Yes most controllers can be modded by simply replacing fets and adjusting the shunt. Sometimes one has to beef up the traces on the circuit at the same time. If you want to put a higher voltage in it than it was designed for, you will also have to change the caps from 60Vmax to 100V caps.

 

[cajunjay]

Thanks for the reply.

I dont need to up the volatge at all 48v is what I will run at, the changing of the FET's and modding the shunt can be done but last time I had to solder in a resisitor to stop the motor from cutting out. (C20)

Maybe you are not familiar with these exact controllers but im pretty sure its a common problem that has been discussed about ecrazymans keywin controllers just a bit hard to locate on the forum. You are right in saying I could get these controllers ready to go off Lyen or other members here but I want to learn how to do this myself

 

[el_walto]

I upgraded a cheap controller once, replaced the fets and adjusted the shunt. I did not have to change any other components. Thats all the info i have, sorry no specifications.

This should work on most controllers without changing any other components. You generally only need to change resistors and caps if you are changing the voltage range of the controller. (All that info from my limited knowlege, hopfully others can confirm and give you more specifics)