Originally Posted by billp56

Thanks for the input, guys. You are right about the batteries. I bought these "UltraFire 18650 3.7V Rechargeable Battery 6000mAh Black" cells from ebay ($140 for 120 cells). I should have done more research before picking them up because they do not deliver anywhere near what they claim. My BMS has a fixed over-discharge threshold of 2.9V per cell so that should let me take the pack down to 37.7V. This is the controller I bought: 48V 1000W bike motor controller. It has a lot of features like low voltage cutoff that I do not know how to adjust because it came with no instructions. I think I will email the seller and see if I can get a manual from them. I understand these are hard to come by as many of them are generic Chinese controllers. The controller also has a speed limiter. I wonder how I can determine if that is in use.