Hi all,
Last month I got some good advice on mounting my 4x12V-18AH LA batteries to my 48V 1000W front hub motor on my bike. That part worked out well. I took it out a few times and got great results. Good speed and torque. I don't have any measuring equipment but it was enough, by far, for my needs. Suddenly I noticed a reduction of speed and hill climbing performance. This was after about 4 outings of maybe 4 miles each. I couldn't even get it to climb a small incline at a busy intersection without quite a bit of hard pedaling. The battery indicator which came with the kit shows all three LED's lit, even under load. The battery charger has only a green LED for charge and a red one for input power. Both are lit as soon as I plug the charger into my batteries. I don't notice any noticeable friction on either wheel and no unusual sounds. It's just slow and seems to have maybe a third of the torque it used to have.
This kit is the same one sold by Xcceseries on EBAY. Unfortunately, I don't have a VOM to test anything (One is on the way), but from a visual inspection I don't see any evidence of loose, overheated or broken connections. This controller does have 2 unused connectors coming out of it but the manual doesn't explain what they are for. I'm assuming one might be for pedal assist, the other is a 2 pin connector which I have no clue about. It was running fine with the connections the way they are. Maybe I lost a MOSFET in the controller? I don't know..
Any help would be appreciated.

Well, I got it going. Now the bike is up to full speed again. Turns out the culprit was the crummy charger that came with the kit. I received my cheap meter from China and determined that the output of the charger was less than the batteries and when connected, it just read the battery voltage which appeared to be low. Actually I was fighting three problems. 1 - Power indicator that came with kit showed full charge. 2 - The led on the charger showed green indicating full charge. 3 - The crummy meter I bought was way off calibration. I got it close using the internal adjustment while measuring 4 different 1.5 vdc batteries. Not perfect, I know. Live and learn. You really do get what you pay for! For what it's worth I bought a Save A Battery 2365-48 48-Volt Battery Charger and Maintainer from Amazon and was pleased with the results.