Rubbee consists of a polyurethane roller wired to a 14.4-volt battery pack. The doohickey presses the roller against the back tire of the bike, propelling it with the force of wheel-on-wheel friction ...

like this rather cool electric quad It’s an impressive build, including two 1 kW motors and a tilting turning system that makes it more maneuverable than most quad bikes. It has big ...

If you’re [James Bruton], you design and build a mini electric bike. Being a prolific builder, [James] already had the parts he needed. Some of them were left over from previous projects ...