We fitted a KU123 controller to Saneagle's bike. It works OK except it cuts our at 35.5v when his battery is only half empty, so he only gets 10aH out of his 20aH 36v battery. 35.5v is the LVC for 48v. My memory says that the pair of single red wires is a pair of jumpers to switch between 48v and 36v, but I can't find any reference to this unless there was a label on the actual wires, which have been removed. Can anyone confirm this and which way they should be for 36v? We've tried connected and disconnected directly on the pcb, but it still cuts out at 35.5v, so if you have one of these controllers and your range is a bit low, you need to check for this. The bike works perfectly with a 36v KU93, which will let thebattery give its full 20aH.