Hi there!
Don't know if anyone can help me here or whether it's the right thread to post (plz move if not).
Bought a 1000W 48V Goldenmotor back in 2010.
It's the fat model with the 3 silver rings like
this, but 28" spoke wheel, front.
Can anyone identify the controller and help me to lower the low voltage cutoff. Which resistors to modify?
It somehow looked so similar to the pics here (same case, wires, capacitor placement) but still is different.
It would already help if someone would have a pic of another version, e.g. 36V, for comparing differences.
I've been using it for months @ 72V. Know I shouldn't do that (or at least replace capacitors) but it works fine and provides the last missing small speed gain.
My bike gets ~45km/h @ 48V normal road and load vs. ~55km/h @ 72V ... as city speed limit is 50km/h here and cars always drive 50-60, it's much safer @ 55km/h, the cars (or better car masses) don't overtake you permanently and you've also less trouble with classic mopeds

At 48V extra pedaling was much too hard to gain at least 50km/h.
I use 6 12V 12Ah lead batteries and I already intergrated a complete strong serial/parallel switch system down to 12V for charging with standard car chargers.
It would be easy to switch to 36V 24Ah or even 24V 36Ah without modifications. This would be really nice for travelling longer distances in spite of lower speed.
But unfortunately below 48V nothing works. But using 48V with 6 cells requires permanet switching to discharge the cells symmetrically. 36V would be much less annoying and also still more gain in range. Don't know if 24V is possible but wouldn't focus on that, since my other extra electronics (complete LED light system incl. indicator+brakes, lock system, etc.) just work 36V-72V at the moment, too.
Any other possibility would be upgrade to 96V and switch between 96V and 48V. But I wouldn't expect the controller to handle THAT. And since 48V->72V weigth is already at absolute limit one man can lift up/down cellar stairs, another 8kg simply not possible as I couldn't handle THAT
I would appreciate any help to lower the LVC. Can provide more pics/information if necessary. Oscilloscope could be organized with some obstacles.
Thanks a lot!