Originally Posted by
nfmisso
Use the one for which you have a matching battery. (48V or 36V). The battery is half the parts cost of a conversion - more if you are looking for long range.
If you don't have the battery, 48V is fractionally more efficient, and typically pack more Wh in a given case size.
I will build the Battery my self, i got a lot of brand new LG 3500 mAh 18650 Cells