Hello,

I'm Bill from the SF Bay Area and I just joined the forum. I just completed my first build and I'm happy to say the she runs! But, not as well as I expected. I'm running a 1000W freewheel with a 1000W controller and custom built 48V battery with BMS. I was really expecting to be going much faster on such a large motor, but I seem to be topping out around 20mph (but I will say, it busts up hills with very little effort). Also, when the battery gets down to around 49V, it can no longer power the motor. Is this normal? The battery will discharge to 49V on just 30 min of full throttle.

I am wondering if anyone has any input on whether there may be something wrong with my build or if I just miscalculated. The battery is comprised of 6000mAh 18650 cells (9 cells in parallel x 13 series). When I calculated the capacity, I multiplied 6Ah * 9 cells = 56Ah. 56Ah * 48V = 2688Wh. So with a 1000W motor, I was thinking that should last about 2.5hrs of full throttle on a full charge. Is my math correct? Any help would be greatly appreciated.