Instead , the cranks are connected to an alternator , which continually recharges the battery that powers the 250 - watt motor at the rear wheel .
There is no mechanical connection between the cranks and rear wheel at all .
The cranks are connected to an alternator , which continually recharges the battery that powers the 250 - watt motor at the rear wheel .
There is no mechanical connection between the cranks and rear wheel at all .