All the data on these motors can be found at
http://www.modelmotors.cz.
You'll see them rated in terms of cell count. The 4130/16 is rated for 16-24 cells. The 4130/20 is rated for 20-30 cells. These are NiCd cells, rated at 1.2 Volts each, and are 1.4 Volts each fully charged. You do the math
