I have just finished building my first bike. Its a 1972 Schwinn Speedster with a Sturmey-Archer 3 speed internal hub and a 36V Wilderness Energy BD36 kit. The install went pretty good aside from a few hickups here and there.
I have put about 10 miles on the motor and all the sudden it started making a grinding sound and just quit working. I popped the case open and found that the brush holding bracket for the positive lead was completely melted causing the brush to flop around which is the cause of the grinding sound. Now at 36V my motor is getting hot enough to melt components within the motor, I was hoping to eventually go to 48V once the motor is proven (and the warranty is over) - How are you guys running at 48V getting away with this? Is my controller passing too much current for this motor to handle?
Ambient air temperature is near 60F and the load wasn't anything too significant besides a few small hills here and there.
Your experience is greatly appreciated and I look forward to participating on this forum.