Electric bikes have increased ... To that end, it uses two small-sized motors connected together with a belt, which together power a friction drive which clamps against the rear tire to spin ...

I'm usually test-driving electric cars, but lately I've been playing with a fun alternative: a clip-on electric motor that converts an ordinary bicycle ... a simple friction drive system, it's ...

he was able to convert a traditional bicycle to electric-drive for around $200. Electric skateboards paved the way for this hack, as it was an outrunner motor that he chose to use as a friction ...