Originally Posted by 2old

20 mph would SEEM (to me) to be max for that kind of trike. You could achieve that (IMO) with a 36V system (depending on your weight, wind and on flat ground). A 48V, 20 ah lead battery will weigh ABOUT (I'm guessing) 40 - 50 pounds and you need to decide where to put it. All hub motors aren't the same, but for your price range there probably isn't much difference. Also for a front application you should have a steel fork and probably at least one torque arm. I think you should consider a 350w, 36V kit with a geared motor and Lithium battery (you should be able to put this together for $600 -$700, maybe less). If you want a heavy direct drive, inexpensive motor put 48V, 1000w into your browser. Inexpensive, but decent systems from acceries or whatever for $200 -$300, then you just need a torque arm and battery.