These are typically conical pulleys with variable diameters. The motor powers the enter pulley although the output pulley sends power to your wheels through both a driveshaft or CV shafts. You puuuulllll pull the toy backwards and also the motor tightens…..this means you pull it back…hold it…and “let it Go!” https://gregorypuwvv.theblogfairy.com/31959346/5-tips-about-gearbox-cvt-you-can-use-today